The error codes and descriptions below are from the ES Controller used all units with touch screen up to the new R290 units.
| Failure code | Failure name | Failure origin and plausible causes | Failure description | Actions to be taken – suggested solutions |
|---|---|---|---|---|
| F08 | Not in use! | |||
| F13 | Room temp. sensor failure | Indoor unit – Wiring, faulty component | When the line controller is set to room temperature control mode or the room temperature curve fine-tuning function is active, and the room temperature sensor is detected to be disconnected or shorted, the unit will report a fault and be shut down; | 1. Poor contact: Based on unit wiring diagram, find the connection of the temperature sensor. Check contact between sensor terminals and PCB terminals if it is poor. If yes, pull the sensor out and plug it back in. If the fault is cleared, pull the sensor leads toward the electrical box to ensure that there is no tension between the sensor terminals and PCB terminals. If the fault is not cleared, then check according to point 2; 2. Main control board problem: Pull the sensor out from control board and reinsert a new sensor to see whether the failure on display is cleared or not. If the fault is not cleared, it means that the main control board is damaged. Please replace the main control board. If it is cleared, first test the intermediate connecting wire whether there is a short circuit or a broken circuit. If yes, replace the intermediate connecting wire. If no, replace the room temperature sensor; |
| F14 | Hot water temp. sensor failure | Indoor unit – Wiring, faulty component | When the hot water mode is active, if a disconnected or shorted hot water temperature sensor is detected, the unit will report a fault and be shut down; | 1. Check if sensor is in place. If not, put sensor back and insulate it. 2. Poor contact: Based on unit wiring diagram, find the connection of the temperature sensor. Check contact between sensor terminals and PCB terminals if it is poor. If yes, pull the sensor out and plug it back in. If the fault is cleared, pull the sensor leads toward the electrical box to ensure that there is no tension between the sensor terminals and PCB terminals. If the fault is not cleared, then check according to point 3; 3. Main control board problem: Pull the sensor out from control board and reinsert a new sensor to see whether the failure on display is cleared or not. If the fault is not cleared, it means that the main control board is damaged. Please replace the main control board. If it is cleared, first test the intermediate connecting wire whether there is a short circuit or a broken circuit. If yes, replace the intermediate connecting wire. If no, replace the hot water temperature sensor; |
| F15 | TC (heating/cooling) water temperature sensor failure | Indoor unit – Wiring, faulty component | When heating/cooling mode is active, if a disconnected or shorted TC sensor is detected, the unit will report a fault and be shut down; | 1. Poor contact: Based on unit wiring diagram, find the connection of the temperature sensor. Check contact between sensor terminals and PCB terminals if it is poor. If yes, pull the sensor out and plug it back in. If the fault is cleared, pull the sensor leads toward the electrical box to ensure that there is no tension between the sensor terminals and PCB terminals. If the fault is not cleared, then check according to point 2; 2. Main control board problem: Pull the sensor out from control board and reinsert a new sensor to see whether the failure on display is cleared or not. If the fault is not cleared, it means that the main control board is damaged. Please replace the main control board. If it is cleared, first test the intermediate connecting wire whether there is a short circuit or a broken circuit. If yes, replace the intermediate connecting wire. If no, replace the TC temperature sensor; |
| F16 | Water outlet temp. sensor failure | Indoor unit – Wiring, faulty component | When display detects that the water outlet temperature sensor is disconnected or shorted, it will report a failure but unit will not be shut down. Unit keeps working with water inlet temperauter + stop delta T as target temperature. If both the water inlet and outlet water temperature fails, it will be shut down; | Note: For split unit, indoor control board and water outlet temperature sensor are in indoor unit. For monoblock unit, indoor control board is in indoor unit and water outlet temperature sensor is in outdoor unit. 1. Poor contact: Based on unit wiring diagram, find the connection of the temperature sensor. Check contact between sensor terminals and PCB terminals if it is poor. If yes, pull the sensor out and plug it back in. If the fault is cleared, pull the sensor leads toward the electrical box to ensure that there is no tension between the sensor terminals and PCB terminals. If the fault is not cleared, then check according to point 2; 2. Main control board problem: Pull the sensor out from control board and reinsert a new sensor to see whether the failure on display is cleared or not. If the fault is not cleared, it means that the main control board is damaged. Please replace the main control board. If it is cleared, then check according to point 3； 3. Sensor problem： 3.1.For split unit, pull sensor out from control board and use multi meter to detect resistance of sensor. If the resistance value is infinite or no resistance value, then replace the sensor. 3.2. For monoblock unit, check according to 3.1. While for unit with an intermediate connection cable (and the indoor panel is not inside the outside unit), the status of the intermediate connection cable should also be checked; |
| F21 | Three-way valve mixing temp. sensor 1 failure | Indoor unit – Wiring, faulty component | When the mixing valve function is valid, if the mixing water temperature sensor 1 is detected to be disconnected or short circuit, F21 is reported, but the unit does not stop. | 1. Poor contact: find the interface of the temperature sensor according to the wiring diagram , check if the sensor terminals and PCB terminals is poor contact, pull it out and then plug it back in again, if the failure is cleared, then pull longer the sensor toward the electrical box to ensure here is no tension between the sensor terminals and PCB terminals; if the failure is not cleared, then check according to step 2; 2. Main PCB problem: pull the sensor out of the circuit board and plug in a temporary sensor, observe whether the failure on the operation panel is cleared or not, if the failure is not cleared, it means that the main PCB is damaged, replace the main PCB；if the failure is cleared, first check if the intermediate connecting wire is in short circuit or in broken circuit, if there is, replace the intermediate connecting wire, if there is not, replace the room temperature sensor; |
| F22 | Three-way valve mixing temp. sensor 2 failure | Indoor unit – Wiring, faulty component | When the mixing valve function is valid, if the mixing temperature sensor 2 is detected to be disconnected or short circuit, F21 is reported, but the unit does not stop. | 1. Poor contact: find the interface of the temperature sensor according to the wiring diagram , check if the sensor terminals and PCB terminals is poor contact, pull it out and then plug it back in again, if the failure is cleared, then pull longer the sensor toward the electrical box to ensure here is no tension between the sensor terminals and PCB terminals; if the failure is not cleared, then check according to step 2; 2. Main PCB problem: pull the sensor out of the circuit board and plug in a temporary sensor, observe whether the failure on the operation panel is cleared or not, if the failure is not cleared, it means that the main PCB is damaged, replace the main PCB；if the failure is cleared, first check if the intermediate connecting wire is in short circuit or in broken circuit, if there is, replace the intermediate connecting wire, if there is not, replace the room temperature sensor; |
| F23 | Not in use! | / | / | / |
| F24 | Not in use! | / | / | / |
| F25 | Not in use! | / | / | / |
| F26 | Not in use! | / | / | / |
| F27 | Indoor EEPROM failure | Indoor unit – Indoor PCB is broken | When the EEPROM data of the indoor main PCB cannot be read, F27 is reported and the unit is shut down. | 1.Replace the indoor PCB; |
| F28 | Water pump PWM signal failure | Indoor unit – Wiring, faulty component | When the P0 water pump is set to be controlled by PWM pump, if without feedback signal is detected after the water pump runs for 120 seconds, F28 is reported and the unit is shut down. | 1. Check whether the water pump PWM signal cable is loose or poor contact. – When unit is in Off state, pull it out and then plug it back in again, and then repower. – Run the unit, observe whether the failure is cleared after the water pump runs for 2 minutes. At the same time, within 2 minutes, use DC voltage gear of the multimeter to measure if the the feedback voltage of the water pump PWM terminal on the indoor main PCB. – If Voltage＞0V, replace the indoor main PCB, – If not, replace the PWM signal cable, If error still not cleared, replace the water pump; |
| F29 | Mixing valve 1 failure | Indoor unit | When the mixing valve function is valid, in the heating mode, the mixing water temperature 1-set temperature is in system 1 > 4℃; or in the cooling mode, the mixing water temperature 1-set temperature in system 1 < 4℃, and the mixing valve is adjusted to 0V and keep for 10 minutes, then three-way-valve 1 failure is reported, the secondary water pump is shut down, but the heat pump will keep operating. | 1. Check whether the actual TC temperature for heating is lower than the mixing water temperature in the water system diagram of the operation panel, if so, check the installation position of the mixing water temperature sensor; or check if the floor of the room is exposed to direct sunlight so resulting in a high mixing water temperature, if so, can ignore this failure, because when there is no direct sunlight exposed, after the mixing water temperature drops the failure will be cleared automatically; 2. Check whether the actual TC temperature for heating is higher than the mixing water temperature in the water system diagram of the operation panel, if so, keeping checking as following: 2.1. According to the wiring diagram, use a multi meter (DC voltage gear) to measure whether the 24 V power supply of the mixing valve is normal or not, if not normal, check whether the connecting cables between the mixing valve and the main PCB is loose or disconnected; 2.2. Power off and restart the unit, according to the wiring diagram, use a multi meter (DC voltage gear) to measure if the control signal of water mixing valve decrease from 5 V down to 0 V in the way about every 20 seconds decrease 0.5 V, if so, higher the setting temperature of the mixing temperature (5℃ higher than the current mixing temperature). Then test if the mixing valve control signal increase in about every 20 seconds increase 0.5 V, at the same time, observe if the mixing water temperature have tendency to increase, if not, either the mixing valve coil is abnormal, or the mixing valve is stuck. 3. Replace the valve coil. When unit is in Off state, replace the cables and coil. If there is an extension cable in the middle, can first check if the extension cable is poor contact: disconnect both ends of the extension cable, in one end of the cable connect 0 V and 10 V together, and connect 0 V with 24 V together, then use the on and off gear of multi meter to measure the other end of the cable between 0 V and 10 V, 0 V and 24 V to see whether it is conducting, if it is conducting, replace the valve coil, if it not conduct, replace the intermediate connecting cable first then repeat the operation in step 2.2; |
| F30 | Mixing valve 2 failure | Indoor unit | When the mixing valve function is valid, in the heating mode, the mixing water temperature 2-set temperature is in system 2 > 4℃; or in the cooling mode, the mixing water temperature 2-set temperature in system 2 < 4℃, and the mixing valve is adjusted to 0V adn keep for 10 minutes, then three-way-valve 2 failure is reported, the secondary water pump is shut down, but the heat pump will keep operating. | 1. Check whether the actual TC temperature for heating is lower than the mixing water temperature in the water system diagram of the operation panel, if so, check the installation position of the mixing water temperature sensor; or check if the floor of the room is exposed to direct sunlight so resulting in a high mixing water temperature, if so, can ignore this failure, because when there is no direct sunlight exposed, after the mixing water temperature drops the failure will be cleared automatically; 2. Check whether the actual TC temperature for heating is higher than the mixing water temperature in the water system diagram of the operation panel, if so, keeping checking as following: 2.1. According to the wiring diagram, use a multi meter (DC voltage gear) to measure whether the 24 V power supply of the mixing valve is normal or not, if not normal, check whether the connecting cables between the mixing valve and the main PCB is loose or disconnected; 2.2. Power off and restart the unit, according to the wiring diagram, use a multi meter (DC voltage gear) to measure if the control signal of water mixing valve decrease from 5 V down to 0 V in the way about every 20 seconds decrease 0.5 V, if so, higher the setting temperature of the mixing temperature (5℃ higher than the current mixing temperature). Then test if the water mixing valve control signal increase in about every 20 seconds increase 0.5 V, at the same time, observe if the mixing water temperature have tendency to increase, if not, either the mixing valve coil is abnormal, or the mixing valve is stuck. 3. Replace the valve coil. When unit is in Off state, replace the cables and coil. If there is an extension cable in the middle, can first check if the extension cable is poor contact: disconnect both ends of the extension cable, in one end of the cable connect 0 V and 10 V together, and connect 0 V with 24 V together, then use the on and off gear of multi meter to measure the other end of the cable between 0 V and 10 V, 0 V and 24 V to see whether it is conducting, if it is conducting, replace the valve coil, if it not conduct, replace the intermediate connecting cable first then repeat the operation in step 2.2; |
| E02 | Outdoor main PCB and comp driver PCB communication failure | Failure code shown on indoor unit display. Failure signal comes from outdoor unit. Plausible cause: Wiring, faulty component. | When there is no communication between the outdoor main PCB and comp driver PCB for 30s, the outdoor main PCB will report a failure and unit will be shut down while the driver PCB will also stop working. | There is different PCB in single phase and three-phase units. 1. Cut the power of unit and open the outdoor unit's electrical box. Check if the unit has separate PCB s (Main PCB and compressor driver PCB) If so whether the communication cable between the outdoor main PCB and compressor driver PCB is loose. Reinsert the communication cable and ensure that it is correctly inserted into the communication ports. 2. Restart the unit and observe if there are indicator lights blinking on the compressor driver PCB. On single phase unit,use a multi meter (set to AC voltage mode) to measure the input voltage of the driver PCB between phases. Should be constant between (220-240 V AC) For three-phase units, use a multi meter (set to AC voltage mode) to measure the input voltage of the driver PCB between phases. Should be constant between (380-415 V AC) to verify its consistency with the power supply. If the power supply is normal for each phase, replace the compressor driver PCB. 3. If the communication failure persists even after replacing the compressor driver PCB, replace the outdoor main PCB. |
| S01 | Cooling anti-freezing protection | Failure code shown on indoor unit display. Failure signal comes from indoor unit. Plausible cause: – Sensors not connected or broken, – Insufficient flow – Refrigerant leakage | In Cooling mode, if the evaporating temperature (Tp) is detected less than 1℃ after the compressor runs for 3 minutes, unit will report a failure and shut down; | 1. Check settings and installation. – If temperature for cooling is set to low, for example 7°C, it can cause this error. Change the setting to a higher value. – Hydrolic piping between outdoor unit (monobloc) or between indoor unit (split) and buffer tank is to long or not right dimension (refer to installation manual). – Check the position of the TC sensor in the buffer tank (refer to installation manual). 1. Check the temperature difference between the inlet (TUI) and outlet (TUO) water of the unit. – If it exceeds 8℃, check and clean the filter of the water system. – Secure that P0 water pump is running at maximum speed. 2. Check if the outlet water temperature (TUO) is 7°C or lower. 3. For split unit, check whether the refrigerant pipe is over 15 meters and additional refrigerant is charged. If not, charge refrigerant according to the length of piping. 4. For split unit, make a leakage detecting test. And if needed recover the refrigerant and compare it to specified refrigerant amount for the specific unit. Repair any detected leakages. Please refer to product data och nameplate on unit for refrigerant levels. 5. If the above troubleshooting are not functioning, the failure can be caused by EEV. Please refer to the "electronic expansion valve troubleshooting section". |
| S02 | Water flow switch protection | Failure code shown on indoor unit display. Failure signal comes from indoor unit. Plausible cause: – Air in system, – Low pressure – Insufficient flow – Wiring – Broken component | When the system pump (P0) starts to run for ≥ 20 seconds, and the water flow switch is open ≥ 10 seconds, unit will report a failure and shut shown; This error will automatically reset after 2-3 minutes. I error occurs 3 times within 30 minutes then it will trigger S10 which stops unit permanently until re-powered | 1. Check whether system is: – Well air purged, no air in the hydraulic system. – Whether the water pressure is above 1,5 bar in the hydraulic system. – Whether all valves are open in the hydraulic system. – Whether the dirt or magnetic filter is blocked or not in the hydraulic system. – Whether the water pump is running correctly – That the water flows in the correct direction after the unit is turned on. – Pipe dimension is correct (not to small). – Hydraulic piping between outdoor unit (monobloc) or between indoor unit (split) and buffer tank is to long or not right dimension (refer to installation manual). – Wires between indoor PCB and water flow switch 2. If alarm is only occurring in one of the working modes (DHW or Heating/Cooling). but not the other then the problem must be a flow problem in the circuit connected to that specific mode. – If in DHW mode, check hydraulics after the diverting vale (included the diverting valve) in direction of DHW. – If in Heating/cooling mode, check hydraulics after the diverting vale (included the diverting valve) in direction of heating/cooling system. If the problem still cannot be solved, replace the water flow switch and restart the unit. |
| S03 | Water flow switch failure | Failure code shown on indoor unit display. Failure signal comes from indoor unit. Plausible cause: – Wiring – Broken component | If (P0) stops and the water flow switch detects flow in the system for 5 minutes, unit will report a failure. Unit will not start. | 1. Water flow switch checking: – When unit is off or stops, pull the water flow switch cable out from the indoor PCB and use a multi meter (on/off) to check the water flow switch. – If it’s closed, replace the water flow switch. – If it’s open, replace the indoor PCB. 2. Check for external factors: – If there is an external water pump working inline, in the same water system (if no buffer or before buffer) the system water pumps needs to be synchronized or removed. |
| S04 | Indoor unit communication failure | Failure code shown on indoor unit display. Failure signal comes from indoor unit. Plausible cause: – Wiring – Broken component – Broken indoor PCB – Power supply | When there is no communication between the operation panel and the indoor main PCB for 2 minutes, unit will report a failure and shut shown; | 1. Check communication cable (A/B) between operation panel and indoor PCB. Pay attention to the socket connector on back of the display and also connectors on cables (model dependent). 2. Check the 24 V power supply: – Check that operation panel receives stable 24 V DC power, if power supply is below 20 V, check cables, connectors and power output of the transformer (230V AC/24 V DC) If transformer doesn't have stable output – exchange it. If S04 occurs in combination with S05: – Change the operation panel |
| S05 | Outdoor unit communication failure | Failure code shown on indoor unit display. Failure signal comes from indoor unit. Plausible cause: – Wiring – Broken component – Broken indoor PCB – Power supply | Whenever there is no communication between the operation panel and the outdoor main PCB for 2 minutes, unit will report a failure and shut shown; | 1. Test the root cause of communication failure. – If the the error is present at all times check according to steps 2, 3 and 4 below. – If the the error occurs only when outdoor unit is running or starting up confirm whether there is a G port on the A/B communication terminal of the outdoor unit or not. (Do not connect G to ground or chassis). – If yes, connect the G line of the outdoor unit to the G port at the communication port of the indoor main PCB, and then restart the unit, – If not, continue to next step below. – If the communication failure still exists, check whether the communication wire in the indoor and outdoor is separated from the strong power cable. 2. Wiring problems: – Check whether the A/B port of the indoor and outdoor unit communication line has not been reverse connected or have poor contact, use a multi meter to check the cable (on and off gear). Cut the power to the unit and short-circuit the A/B on one end and measure the connection on the other end, if the line is broken, then replace the communication line. 3. Power supply problem: – Check whether the power supply of the outdoor main PCB is 230 VAC and the main PCB has a blinking light. – If power supply is correct continue to next step. – If power supply in not correct, check power supply to unit. 4. Disconnect the power, unplug the DC fan from the main PCB, and repower the unit to verify that the communication failure is not caused by a damaged fan motor. If none of the above helps it is likely a hardware problem with the outdoor main PCB which needs to be replaced. If S05 occurs in combination with S04: – Check the operation panel |
| S06 | Cooling outlet water temp. too low protection | Failure code shown on indoor unit display. Failure signal comes from indoor unit. Plausible cause: – Flow – Sensors faulty | In cooling mode, if TUO < 5 degrees, unit will report a failure and shut shown. | 1. Restart unit, check the inlet and outlet water temperature δT (between TUO and TUI) on the system diagram on the operation panel. If it is greater than 8 degrees. – Check whether the pump speed is set to high speed (it is recomended to always have circulation pump in high speed in cooling mode) – Check whether the filters are clean. – Check pressure in the hydrolic system (1,5Bar) 3. Secure that TC sensor is correct installed. – TC in upper part of buffertank – Ensure good heat transfer to the sensors 4. Secure that TUO is correct installed. |
| S07 | Heating/DHW outlet water temp. too high protection | Indoor unit – Flow and/or sensors faulty | If the actual outlet water temperature (TUO) is higher than the maximum outlet water temperature of the heat pump in heating or DHW mode, unit will report a failure and shut down the compressor. Electrical heater can continue to work. Unit will recover when TUO is lower than maximum outlet water temperature If external heating sources connected to buffer not controlled by heat pump causing the tempereature in the DHW tank to get higher than the maximum temperature. Note: Max temp is depending on the current outdoor temperature (envelope). | In general: Temperature setting to high for heating or DHW modes. False temperature sensor readings: – Secure that TC and TW sensor is correct installed. – TC in upper part of buffertank. – TW in the upper part of the DHW tank. – Ensure good heat transfer to the sensors Flow issues: – Dirty filter. – P0 speed setting (recomended HIGH). – Pipe distance to long and to many elbows between outdoor unit and DHW tank. – Partially closed hand valves Diverting valve malfunction: – Stuck because of mechanical issues – Blocked by dirt or other debree – Motor broken – Power supply to motor In DHW mode: 1. Restart the unit and check the inlet (TUI) and outlet (TUO) water temperature and water tank TW temperature. If the inlet (TUI) water temperature is higher than the TW temperature, this indicates low heat transfer which causes S07. (Normally, the TW temperature is always higher than the inlet (TUI) water temperature), Low heat transfer can be caused by: – To small coil in DHW tank – To small heat exchanger for DHW As a temporary solution, the hot water ECO mode can be turned on to see if it is possible to alleviate the heat exchange problem of the water tank. If the problem can not be solved, it is necessary to replace the coil of water tank with a larger area as recommended; Coexistence of heating and hot water modes. 1. Observe the inlet and outlet water temperature δT of heat pump, if it is more than 8 degrees, please check whether the speed setting of the water pump is high speed . If it is low speed, please adjust it to medium or high speed. And at the same time, please check whether the filter in the water system is clogged; 2. Check the difference between the TC temperature and the outlet water temperature. If the temperature difference is more than 5 degrees (the outlet water temperature is higher than the TC), check whether the TC temperature sensor is installed in the middle or upper part of the buffer tank; |
| S08 | Defrost three-time failure | Indoor unit – Flow, sensors faulty. Secondary side flow | When S09 (Defrost outlet water temp. too low protection) is triggered 3 times, unit will report a failure and be shut shown. This failure can not be recovered untill repower; | 1. If the ambient temperature is below 0℃ and the water temperature is below 10℃, when the unit starts up and runs for the first time with defrost, water outlet temp can be too low can result in this protection. 2. Restart heating mode and observe the inlet and outlet water temperature δT during the heating operation. If it’s more than 8 ℃ and the set temperature is low (below 30 ℃), check whether the water pump speed is high speed (if it is low, please adjust to medium or high speed). Also check whether the filter is clogged in the water system. It is better to increase the set temperature to more than 32 degrees; 3. Check whether the unit is with heavy frost (evaporator frost thickness greater than 8 mm or ice fully covers), resulting in defrost time too long which cause the water temperature too low. In this case, manually remove the frost on the evaporator with hot water, and then check the cause of serious frost; 4. If the unit is newly installed, the distribution system is floor heating and fully open, it’s recommended to close 2/3 of the water pipes of the floor heating to let the heat pump raise the water temperature as soon as possible. After the water temperature goes above 30 degrees, then open some more water loops. Keep this cycle constantly to raise the water temperature of heat pump to medium temperature. |
| S09 | Defrost outlet water temp. too low protection | Indoor unit – Flow, sensors faulty. Secondary side flow | During defrost, if TUO < 15 degrees, unit will report a failure and stop defrosting; | 1. If the ambient temperature is below 0℃ and the water temperature is below 10℃, when the unit starts up and runs for the first time with defrost, water outlet temp can be too low can result in this protection. 2. Restart heating mode and observe the inlet and outlet water temperature δT during the heating operation. If it’s more than 8 ℃ and the set temperature is low (below 30 ℃), check whether the water pump speed is high speed (if it is low, please adjust to medium or high speed). Also check whether the filter is clogged in the water system. It is better to increase the set temperature to more than 32 degrees; 3. Check whether the unit is with heavy frost (evaporator frost thickness greater than 8 mm or ice fully covers), resulting in defrost time too long which cause the water temperature too low. In this case, manually remove the frost on the evaporator with hot water, and then check the cause of serious frost; 4. If the unit is newly installed, the distribution system is floor heating and fully open, it’s recommended to close 2/3 of the water pipes of the floor heating to let the heat pump raise the water temperature as soon as possible. After the water temperature goes above 30 degrees, then open some more water loops. Keep this cycle constantly to raise the water temperature of heat pump to medium temperature. |
| S10 | Water flow switch failure | Indoor unit – Wiring, broken component | When the unit has 3 consecutive S02 protection within 30 minutes, S10 will be reported. | Refer to the troubleshooting of water flow switch protection (S02). |
| S11 | Cooling anti-freeze failure | Indoor unit – | When the unit has 3 consecutive S01 protection within 30 minutes, S11 will be reported. | Refer to the troubleshooting of cooling anti-freeze protection ( S01). |
| S12 | Floor preheating failure | Indoor unit – | During the operation of floor preheating , the running time of a certain stage exceeds the specified time, S12 will be reported and unit will exit preheating operation, while the unit can still operate in normal modes; | 1. Check the recorded data of floor preheating to figure out where the anomaly is. Depending on the conditions of floor drying at site, choose if unit should run floor preheating again; 2. Tc (Heating/cooling Temp. Sensor) installation position is not suitable which results in temperature reading deviation. Check whether the temperature difference between Tc (Heating/cooling Temp. Sensor) and the actual temperature is too much (over 2℃); |
| S13 | Four-way valve failure | Indoor unit – Ambient sensor broken, wiring, broken component | When the four-way valve detection function is turned on, in heating or hot water mode, after the unit is running for 10 minutes, unit will detect temperature difference between ambient temperature and outdoor coil temperature for 2 minutes. When the ambient temperature value is lower than outdoor coil temperature, the unit will be locked up with failure reported and cannot be recovered until repower; | 1. When unit is off, check the value of ambient temperature and the outdoor coil temperature through the operation panel and confirm if they are of same value. If yes, follow the next steps. If not, use a hot wet towel or wet paper napkin wrapped around the ambient temperature sensor and check the change of ambient temperature through operation panel. If the ambient temperature remains without change while outdoor coil temperature changes, these two sensors can be connected oppositely. Please correct them according to the wiring diagram; 2. Wiring Problems: According to the wiring diagram, check whether the wiring of four-way valve coil is fine on PCB; 3. When the unit is running for heating and the air blowing outdoor unit is hot, four-way valve coil can be defective. Alternatively, by switching back and forth between the heating and the cooling modes (running for about 3 minutes in each mode), listen to the four-way valve if there is a sound of "Da". If not, replace the four-way valve coil. If yes, check the surface of four-way valve whether it is uneven which may result in that pin of valve does not work. If so, the four-way valve needs to be replaced. |
| S14 | Three-way valve failure | Faulty pipe installation, sensors wiring, sensors installation | When the three-way valve detection function is turned on, in heating or hot water mode, when Tc (Heating/cooling Temp. Sensor) or Tw (DHW Temp. Sensor) temperature value is higher than water inlet temperature for over 12℃, the unit will report a fault and be shut down; | 1. Check and confirm if water connections of the heating and DHW are wrongly connected. Try to reverse the control signal lines of the three-way valve which are for heating and DHW, then observe whether the unit will operate normally; 2. Check and confirm if Tc (heating/cooling temp. sensor) and Tw (DHW temp. sensor) are connected oppositely. Pull out the Tw sensor from water tank and then hold it in hand and observe whether the hot water temperature sensor value follows the change. If the change is on Tc value instead of Tw, reverse the Tc and Tw sensor connections according to the wiring diagram. 3. Check if the Tc or Tw sensors has fallen off, causing the inaccurate temperature reading. If yes, install the Tc or Tw sensor correctly; |
| S15 | Not in use! | / | / | / |
| S16 | Not in use! | / | / | / |
| S17 | Not in use! | / | / | / |
| S18 | Not in use! | / | / | / |
| S19 | Not in use! | / | / | / |
| S20 | Not in use! | / | / | / |
| S21 | Water flow failure | Indoor unit – Flow, | When the unit has 3 consecutive insufficient water flow protection ( P23) within 30 minutes, S21 is reported and unit is shut down and cannot be startup unless re-power. | Refer to the troubleshooting of insufficient water flow protection ( P23). |
| P01 | Over current Protection | Indoor unit – Wiring, flow, | When the unit detects that the input current is higher than the value set by the Eeprom of the external machine, the unit will report a fault and shutdown for protection. | This protection is generally caused by excessive system load. You can power on again and observe the operation of the unit: 1. If the temperature difference between the inlet and outlet water is greater than 8 degrees during operation, check whether the water pump speed is set to high speed (if it is low speed, please adjust to medium speed or high speed), and also check whether the filter in the water system is blocked; 2. If it is triggered in the hot water mode, you can confirm whether the domestic water tank coil is too small (the minimum heat exchange area is 3㎡). If it is too small, it may lead to low heat exchange capacity, so heat will continue to accumulate, and eventually due to The water temperature rises too fast and the current is too large. You can temporarily turn on the hot water ECO mode to see if it can alleviate the heat exchange problem of the water tank. If the hot water ECO mode cannot solve the problem, you need to replace the coil water tank with a larger coil area (at least 3㎡); 3. During operation, you can observe the difference between the inner coil temperature (TUP) and the outlet water temperature (TUO). Normally, the inner coil temperature is 1 to 2 degrees lower than the outlet water temperature. If TUP is higher than TUO, it may because the heat pump is unable to exchange heat, due to fouling of the plate changer. So the current rises and causes a fault, so as long as the plate changer is descaled and cleaned, the problem can be solved; 4. When triggered in cooling mode, you can check whether the evaporator is dirty or blocked or the heat island effect is caused by the installation position, resulting in high current. You can clean the evaporator, adjust the installation location, or install an discharge duct to eliminate the heat island effect; 5. The electronic control parameters are set incorrectly, resulting in false alarms of the unit. At this point you can try to upgrade the main PCB EEPROM settings. 6. Check whether the input voltage is normal. If it is lower than the rated voltage by more than 10%, the over current protection may be triggered. Please contact the power supplier to adjust the power supply voltage. |
| P02 | Compressor phase current overload protection | Indoor unit – Wiring, flow, | When the driver PCB detects that the compressor phase current exceeds the compressor phase protection current value, the unit will report a fault and shutdown. | This protection is generally caused by excessive system load. You can power on again and observe the operation of the unit: 1. If the temperature difference between the inlet and outlet water is greater than 8 degrees during operation, check whether the water pump speed is set to high speed (if it is low speed, please adjust to medium speed or high speed), and also check whether the filter in the water system is blocked; 2. If it is triggered in the hot water mode, you can confirm whether the domestic water tank coil is too small (the minimum heat exchange area is 3㎡). If it is too small, it may lead to low heat exchange capacity, so heat will continue to accumulate, and eventually due to The water temperature rises too fast and the current is too large. You can temporarily turn on the hot water ECO mode to see if it can alleviate the heat exchange problem of the water tank. If the hot water ECO mode cannot solve the problem, you need to replace the coil water tank with a larger coil area (at least 3㎡); 3. During operation, you can observe the difference between the inner coil temperature (TUP) and the outlet water temperature (TUO). Normally, the inner coil temperature is 1 to 2 degrees lower than the outlet water temperature. If TUP is higher than TUO, it may because the heat pump is unable to exchange heat, due to fouling of the plate changer. So the current rises and causes a fault, so as long as the plate changer is descaled and cleaned, the problem can be solved; 4. When triggered in cooling mode, you can check whether the evaporator is dirty or blocked or the heat island effect is caused by the installation position, resulting in high current. You can clean the evaporator, adjust the installation location, or install an discharge duct to eliminate the heat island effect; 5. The electronic control parameters are set incorrectly, resulting in false alarms of the unit. At this point you can try to upgrade the main PCB EEPROM settings. 6. Check whether the input voltage is normal. If it is lower than the rated voltage by more than 10%, the over current protection may be triggered. Please contact the power supplier to adjust the power supply voltage. |
| P03 | IPM module protection | Indoor unit – PCB failure, component broken | During compressor operation, the IPM module is detected to be over-temperature protected (the protection value is generally 95-100 degrees) or over-current protected, and the unit reports a fault and shutdown; | 1. Refer to the P02 troubleshooting method 2. In cooling mode, please check whether the fan is running normally (whether the speed is low, such as below 500 rpm) or only one fan is running in the dual fan system, if yes please refer to the handling of fan failure, check and replace the motor if needed. If the speed is low, contact the manufacturer for further investigation; 3. In cooling mode, you can check whether the evaporator is dirty or blocked or the heat island effect is caused by the installation position, resulting in high current. You can clean the evaporator, adjust the installation location, or install an discharge duct to eliminate the heat island effect; 4. Change for drive PCB |
| P04 | Not in use! | / | / | / |
| P05 | High pressure switch protection | Failure can be triggered by actual high pressure problem or faulty cable or component. | If the pressure exceeds 42 Bar for more then 5 seconds on the high pressure side of the refrigerant system during compressor operation, the high pressure switch is triggered. | 1. If this error comes also with following errors P06 (Compressor speed down due to abnormal high pressure) or/and F12 (Condensing Pressure Failure), then this is a clear indicator that the refrigerant system has a problem with too high pressure. – Confirm that delta T between inlet and outlet is correct. – Confirm that P0 is working normal and set to med/high speed – Check filters on hydrolic side – Confirm that set temp for DHW and heating is not set too high – Air in the hydrolic system – To low pressure in the hydrolic system – Confirm that the condenser is clean – Secure that there is no dirt on the evaporator Check if there is insufficient heat dissipation on the high-pressure side (condensing side) Data recording, after confirming the temperature difference between the inlet and outlet water, shut down and re power the unit. Then the following judgments are made: 2. Confirm the temperature difference between the outlet water temperature and the TC temperature or TW temperature. Normally, the outlet water temperature will be 3 to 5 degrees higher than the TC or TW, if it is more than 5 degrees, please check whether the installation position of the TC and TW sensors is installed in an inappropriate position, the TC or TW should be installed in the middle and upper part of the water tank as far as possible; 3. During the operation of the unit, observe whether the temperature of the inner coil is higher than the temperature of the outlet water. If the temperature of the inner coil is higher than the temperature of the outlet water by more than 3 degrees, check if there is fouling of the plate changer. As long as the plate changer is descaled and cleaned, the problem can be solved; there is scaling in the plate exchange, and it is necessary to clean the water side of the plate exchange to remove the scale; 4. If it occurs in cooling mode,please check for poor ventilation around the unit, you can compare the value between ambient temp. Sensor and real ambient temp, if the difference between the two values is more than 5 degrees, there may be poor ventilation, and you can consider adding an air guide to the unit. So that hot air can F172 be vented in a timely manner; Please check if evaporator is blocked by dirt, clean the evaporator. 2. If the error comes alone (without P06 and/or F12), then it is most likely problem with cable connection of the high pressure switch the high pressure switch itself. 3. If all of above solutions can not solve the problem, the EEV may be abnormal, please refer to the "Electronic Expansion Valve Investigation Part". |
| P06 | High pressure overpressure protection | Indoor unit – Flow, wiring, insufficient air flow around outdoor unit, broken EEV | If the high pressure is higher than the system pressure protection value after the compressor has been started for 1 minute, the unit will report faulty shutdown protection; | 1. Determine if there is insufficient heat dissipation on the high-pressure side (condensing side).After recording the data and confirming the temperature difference between the inlet and outlet water and the outlet water temperature at the time of the unit's protection shutdown, power down and restart the unit to allow the unit to run again, and make the following judgments during the operation process: 1.1. Confirm that the temperature difference between the inlet and outlet water of the unit is within 5 degrees, if it exceeds 8 degrees, please check whether the running gear of the water pump is set to low speed, and try to let the water pump run at medium or high speed to ensure that the water flow is within the normal range; check the filters in the water system, whether there is a dirty blockage, and then clean it; 1.2. Confirm the temperature difference between the outlet water temperature of the unit and the TC temperature or TW temperature, under normal circumstances, the outlet water temperature will be 3 to 5 degrees higher than the TC or TW, if it is more than 5 degrees, please check whether the installation position of the TC and TW sensors is checked off or installed in an inappropriate position, the TC or TW should be installed in the middle and upper part of the water tank as far as possible; 1.3. During the operation of the unit, observe whether the temperature of the inner coil is higher than the temperature of the outlet water. If the temperature of the inner coil is higher than the temperature of the outlet water by more than 3 degrees, there is scaling in the plate exchange, and it is necessary to clean the water side of the plate exchange to remove the scale; 1.4. If it occurs in cooling mode, check for poor ventilation around the unit, check the evaporator of the outdoor unit for dirt and blockage, and clean debris from the outdoor heat exchanger;Check for poor ventilation around the outside unit, compare the outdoor temperature sensor display and the measured outdoor temperature on site to see if there is a big difference, if the difference between the two is more than 5 degrees, there may be poor ventilation, and you can consider adding an air guide to the unit.Circle so that hot air can be vented in a timely manner; 2. If the above troubleshooting is unable to solve the problem, the electronic expansion valve of the refrigerant system may be abnormal, please refer to the "Electronic Expansion Valve Investigation Part". |
| P07 | Initial power-up preheat protection | When the unit is powered on, if the ambient temperature is lower than -5 degrees, the unit will warm up for 30 minutes, report the protection, system will turn on the compressor electric heat tape, and the unit will not be allowed to turn on. | There is no need to deal with it, just leave the unit to warm up for 30 minutes, but with the current version of the program, the line controller will not report a P07 fault; | |
| P08 | High discharge temperature protection | Indoor unit – Wiring, broken sensor, Refrigerant leakage, broken EEV | When the discharge temperature is higher than value of protection shutdown point (generally between 110 degrees and 115 degrees) during unit operation, the unit will report a malfunction shutdown; | Accessories and special tools: discharge temperature sensor, refrigerant, refrigerant leak detector, pressure gauges. electronic scale, multi meter 1. Examine the factors of insufficient refrigerant: 1.1. Under the standby mode which longer than 30 mins, check the refrigerant pressure value, and confirm whether there is serious leakage of refrigerant quantity initially. The judgment way is: whether the saturation temperature corresponding to the pressure value currently displayed, is the same as the ambient temperature, and if it is lower than the ambient temperature by more than 5 degrees, it can be judged that there is a leakage of refrigerant basically; 1.2. For split units, check whether the refrigerant piping exceeds 15 meters and the refrigerant is not replenished; if so, replenish the refrigerant according to the length of the piping; 1.3. You can try to start the machine, and observe the change of low pressure, if the low pressure is too low (i.e. the evaporating temperature is lower than the ambient temperature by more than 10 degrees), and the running time is more than 5 minutes, you can initially judge that it is suspected that the refrigerant is leaking, and you can temporarily add approx. 100-200 g of refrigerant to see whether the low pressure of the system is rising or not. And whether the discharge temperature is dropping. If so, you can find the leakage point in the unit, and make up for the leakage. Re-evacuate the unit and refill the refrigerant according to the refrigerant quantity on the nameplate; 2. Examine the factors of insufficient heat transfer. Please check the error history, if there is no high pressure protection, the effect of poor heat exchange can be ruled out. 3. Sensor problem: Pull out the sensor from the PCB, and use a multi meter to test the function of the resistance, measure the resistance of the sensor, and compare with the table of 50 K temperature – resistance table, if there is a large deviation, then replace the discharge temperature sensor; 4. If the above troubleshooting fails to solve the problem, the electronic expansion valve of the refrigerant system may be abnormal, please refer to "Electronic Expansion Valve Troubleshooting Part". |
| P09 | external coil over-temperature protection | Indoor unit – Evaporator blocked, fan motor malfunction | In the cooling mode, the external coil temperature is higher than the external coil over-temperature protection value (usually around 62 degrees), then the unit reports a fault and shutdown; | 1. In cooling mode, please confirm whether the fan motor is running normally (whether the speed is low, such as less than 500 rpm) or only one fan is running in the dual fan system. If yes, please refer to the solution of fan motor failure, investigate and replace the motor. If the speed is low, please contact the manufacturer for further investigation; 2. In cooling mode, you can check whether the evaporator is dirty or blocked or the heat island effect is caused by the installation position, resulting in high current. You can clean the evaporator, adjust the installation location, or install an discharge duct to eliminate the heat island effect; |
| P11 | Ambient temperature over range shutdown protection | Indoor unit – Broken sensor, wiring, | Heating mode: when the ambient temperature is lower than -25 degrees, or the ambient temperature is higher than 45 degrees, the unit will report a fault and shutdown; Cooling mode: when the ambient temperature is lower than 8 degrees, or the ambient temperature is higher than 65 degrees, the unit will report a fault and shutdown; | 1. Through the multimeter, test if the ambient temperature sensor resistance value corresponding to temperature resistance table, if there is a deviation, then replace the sensor 2. Confirm whether the current actual ambient temperature reaches the limitation point of heat pump ambient temperature. If so, please wait for the ambient temperature reach to a normal range, and the unit will back to normal; 3. Check whether the installation position of the ambient sensor is blocked by ice or exposed to direct sunlight, if so, please protect the ambient temperature sensor, to prevent icing or exposure to direct sunlight; 4. Check whether there is any heat island effect (cold island effect) in the installation position of the unit, and adjust the installation position or install an discharge duct to eliminate the heat island or cold island effect; |
| P12 | environmental frequency limiting protection (EFLP) | Indoor unit | When the unit detects that the heat pump is not allowed to run the highest frequency at the current ambient temperature, the outdoor unit will feedback the ambient frequency limit flag bit, but the unit will still run normally, and the unit will not display this error code. | This error will not show in display, but if target water temperature have a big difference with real water temperature, and unit could not running in high speed, you can consider if it because the ambient temperature is too high, so frequency is limited. You can confirm the accuracy of the ambient temperature check according to the troubleshooting of P11; |
| P14 | Not in use! | / | / | / |
| P15 | Not in use! | / | / | / |
| P16 | Not in use! | / | / | / |
| P17 | Not in use! | / | / | / |
| P18 | Not in use! | / | / | / |
| P19 | Not in use! | / | / | / |
| P20 | Not in use! | / | / | / |
| P21 | Not in use! | / | / | / |
| P22 | Not in use! | / | / | / |
| P23 | Insufficient water flow protection (only with flow sensor) | Indoor unit – Wiring, Flow, air in system, insufficient pressure, circulation pump setting/function | When the water flow is detected to be less than the minimum flow rate (1080L/h for 15KW), the unit will report a fault and shutdown. | 1. Check if the system displays a water flow value that is near or less than the minimum allowable water flow while the pump is running, if yes please check the reasons of insufficient water flow, and find the relatived solution. 1.1. Check that the water system is completely emptied, if the water pressure is above 2 bar, if all valves are opened, if the filter is clogged. 1.2. Check that the water pump operates normally, and water flow is in the correct direction after switching on. 1.3. In running condition, wait for the compressor run for 5 minutes, if the water inlet and outlet temperature difference is in a reasonable range, then remove the water flow sensor, clean it and reinstall it, then restart the unit to exclude the possibility of foreign objects interfering with the detection of the water flow sensor. If the problem still cannot be solved, replace the water flow sensor and restart the unit. 2. If the water flow display value is 0, then check whether the water flow sensor is not contact well; If it is ok, and find the terminal of water flow sensor according to the wiring diagram. Under the condition of ininterrupte the power supply, then use a multimeter (DC level), measuring the water flow sensor power supply is 24V or not. When the water pump is running, the water flow sensor feedback voltage is higher than 0. If yes, then if the supply of water flow is not 24V, if yes then replace the indoor PCB. If the water flow sensor feedback voltage is equal to 0, pull out the water flow sensor cable from the water flow sensor body, and measure whether the terminals at both ends of the connecting wire are on or not. If not, replace the cable; If yes, change the body. |
| E01 | Communication failure between indoor and outdoor units | Failure code shown on indoor unit display. Failure signal comes from outdoor unit. | When the main PCB detects that there is no communication with the master unit (indoor unit) and continues for 120 seconds, the main PCB will report a failure and the compressor will also stop. | 1. Check if the outdoor unit communication connection is normal. 2. Replace the communication cable for outdoor unit. (Maybe the communication cable is broken. If communication cable is broken the indoor unit should report a S05 alarm) |
| E03 | Compressor phase current reading failure | Failure code shown on indoor unit display. Failure signal comes ffrom outdoor unit. | Hardware damage of compressor driver PCB- compressor phase current sampling component | Replace the compressor driver PCB with a new one. |
| E04 | Compressor phase current overload protection | Failure code shown on indoor unit display. Failure signal comes ffrom outdoor unit. Plausible cause: EEProm issue, faulty component | When compressor is operating and the current of the compressor is higher than the protection value of the driver, unit will report a failure and shut shown. | 1. If the compressor is not working at all after unit is ON, the problem can be caused by defective compressor driver PCB. Replace the compressor driver PCB. 3. If the compressor starts but shakes unusually with speeds below 60Hz while this failure occurs, compressor can be defective with a locked rotor. If the unit has separate compressor driver, replace the compressor driver PCB If failure persist – replace the compressor. |
| E05 | Compressor driver PCB failure | Failure code shown on indoor unit display. Failure signal comes from outdoor unit. Plausible cause: Wiring, faulty component | When the compressor driver PCB fails to activate compressor, unit will report a failure and stop. | Check if the wires from the compressor driver PCB to the compressor are securely connected. – If the connection is loose, fasten the cables and restart the unit. – If compressor is still not functioning, unplug the wires on the compressor and measure the resistance between the different terminals of compressor (between U&V / V&W / U&W) to verify if resistance between different terminals are the same or if any circuit is open: 1. If resistance values between different compressor terminals are tested almost equal, try to replace the driver PCB. 2. If the compressor still can not start or shakes unusually after startup with speed below 60Hz while E05 failure happens, compressor can be defective with a locked rotor. Replace the compressor. 3. If resistance values between different compressor terminals are tested unequal or there is any open circuit, compressor is damaged. Replace the compressor. |
| E06 | Compressor driver PCB VDC too high/low voltage failure | Failure code shown on indoor unit display. Failure signal comes from outdoor unit. | When the compressor driver PCB detects an excessively high or low rectified DC voltage, the compressor drive PCB will stop working and the unit will stop. | 1. Use a multimeter to check if the voltage of the power terminal (L1/L2/L3 for three-phase models) is within normal range: – 160V-260V for single-phase units. – 340V-420V for three-phase units. 2. Power off the unit. – Disconnect the DC fan motor from outdoor main PCB. – Repower the unit to check whether the abnormal voltage detection is caused by defective fan motor. – If the failure is cleared, replace the DC fan motor. – If the issue persists, replace the fan driver PCB or main PCB if driver is not separate – If the issue persists, replace the compressor driver PCB |
| E07 | AC current failure | Failure code shown on indoor unit display. Failure signal comes from outdoor unit. | If input current is over 4A when compressor is not working or input current is less than 1A when compressor is running at F4 or higher step, unit will report a failure and stop. | Accessories and tools: refrigerant, Refrigerant leak detector, Pressure gauge, Vacuum pump, electronic scale, Main outdoor control board PCB, Multimeter. 1. Restart the unit. After compressor starts, – check if the evaporating temperature is much lower than normal range (more than 10℃ below ambient) – or if the discharge temperature rises considerably higher than normal range (more than 35℃ above water temperature). If yes, it may indicate refrigerant leakage. – Make a leakage detecting test. – And if needed recover the refrigerant and compare it to specified refrigerant amount for the specific unit. – Repair any detected leakages. Please refer to product data och nameplate on unit for refrigerant levels. For split unit, check whether the refrigerant pipe is over 15 meters and additional refrigerant has been added – If not, charge refrigerant according to the length of piping. For added refrigerant amounts, refer to the installer manual. 2. Use a multi meter to test the live wire of the power input cable to the outdoor unit and check whether the running current is less than 4 A when the unit is standby. If it exceeds 4 A, or if running current is less than 1 A when the unit starts and runs at above 50 Hz, the Main PCB can be defective. Try to replace it. |
| E08 | EEPROM failure | Failure code shown on indoor unit display. Failure signal comes from outdoor unit. Plausible cause: EEProm issue, faulty component | When the outdoor main PCB chip cannot read the parameters or there is a parameter verification error, unit will report a failure and stop. | Power off and restart – if the fault still cannot be cleared after restarting, update EEPROM – if the fault still persists, replace the outdoor main PCB; |
| E10 | Communication failure between fan motor driver PCB and outdoor main PCB | Failure code shown on indoor unit display. Failure signal comes from outdoor unit. Plausible cause: Wiring, faulty component | When the Main outdoor PCB detects that there is no communication with the fan motor driver PCB and continues for 30 seconds, the main PCB will report a failure and the unit will stop. | 1. Turn off the power, – Open the electrical box of the outdoor unit – Check whether the communication cable between the Main outdoor PCB and the Fan motor driver PCB is loose or not according to the wiring diagram. – Disconnect and connect the communication cable. – At the same time, check whether the communication port is inserted in the correct position or backwards according to the wiring diagram. 2. Power on again and measure whether the input voltage of the fan motor driver PCB is consistent with the power supply. – If the power supply is normal, replace the fan motor driver PCB. 3. If the communication failure still exists after replacing the fan motor driver PCB, replace the main PCB. |
| F01 | Outdoor temp. sensor failure – Ta | Failure code shown on indoor unit display. Failure signal comes from outdoor unit. Plausible cause: Wiring, faulty component | When the outdoor main PCB detects a short circuit or disconnection of the outdoor temp. sensor port, the unit reorts a fault and shuts down; | General sensor trouble shooting 1. Poor connection: – Find the connector of the specific sensor according to the wiring diagram. – Secure that sensor terminal and outdoor main PCB terminal connected. – Secure that cable in not streched or damaged. If the error is not cleared, check according to steps as below. 2. Sensor fault: – Disconnect the sensor from the outdoor main PCB and measure the resistance of the sensor with a multi-meter. – If there is no resistance or the resistance is infinite, it means that the sensor is damaged and shall be replaced. 3. Outdoor main PCB fault (if specific sensor is connected to outdoor PCB) – Disconnect the sensor from the outdoor main PCB and re-wire a spare sensor – Observe whether the error on the control panel is cleared. – If the error is not cleared, the outdoor main PCB is damaged and needs to be replaced. |
| F02 | Outdoor coil temp. sensor failure – Tp | Failure code shown on indoor unit display. Failure signal comes from outdoor unit. Plausible cause: Wiring, faulty component | When the outdoor main PCB detects a short circuit or disconnection of the outdoor coil temp. sensor – Tp, the unit reports a fault and shuts down; | General sensor trouble shooting 1. Poor connection: – Find the connector of the specific sensor according to the wiring diagram. – Secure that sensor terminal and outdoor main PCB terminal connected. – Secure that cable in not streched or damaged. If the error is not cleared, check according to steps as below. 2. Sensor fault: – Disconnect the sensor from the outdoor main PCB and measure the resistance of the sensor with a multi-meter. – If there is no resistance or the resistance is infinite, it means that the sensor is damaged and shall be replaced. 3. Outdoor main PCB fault (if specific sensor is connected to outdoor PCB) – Disconnect the sensor from the outdoor main PCB and re-wire a spare sensor – Observe whether the error on the control panel is cleared. – If the error is not cleared, the outdoor main PCB is damaged and needs to be replaced. |
| F03 | Compressor discharge temp. sensor failure – Td | Failure code shown on indoor unit display. Failure signal comes from outdoor unit. Plausible cause: Wiring, faulty component | When the outdoor main PCB detects a short circuit of the discharge temp. sensor or after compressor switching on 10min, detect a broken of discharge temp. sensor, the unit reports a fault and shuts down; | General sensor trouble shooting 1. Poor connection: – Find the connector of the specific sensor according to the wiring diagram. – Secure that sensor terminal and outdoor main PCB terminal connected. – Secure that cable in not streched or damaged. – Secure that the sensor is properly connected to the pipe/insert. If the error is not cleared, check according to steps as below. 2. Sensor fault: – Disconnect the sensor from the outdoor main PCB and measure the resistance of the sensor with a multi-meter. – If there is no resistance or the resistance is infinite, it means that the sensor is damaged and shall be replaced. 3. Turn on the unit and leave it running for 10 minutes. – During the operation check whether the discharge temperature is normal or not. – If the discharge temp. can rise normally and is higher than the water outlet temp. the problem of the poor connection is solved. – If the discharge temp. has been below 0℃ for 10 minutes, then it is necessary to check according to next step. 4. Outdoor main PCB fault: – Disconnect the sensor from the outdoor main PCB and re-wire a spare sensor (NTC50kΩ). – If the ambient temp. is less than 0℃ at this time, hold the spare discharge sensor in hand until the temp. is raised to more than 30℃. – Observe whether the discharge temp. is higher than 0℃. – If so, it means that there is no problem with the outdoor main PCB. – If not, it means that the outdoor main PCB is damaged and should be replaced. |
| F04 | Compressor suction temp. sensor failure – Ts | Failure code shown on indoor unit display. Failure signal comes from outdoor unit. Plausible cause: Wiring, faulty component | When the outdoor main PCB detects a short circuit or disconnection of the suction tempe. sensor port, the unit reports a fault and shuts down; | General sensor trouble shooting 1. Poor connection: – Find the connector of the specific sensor according to the wiring diagram. – Secure that sensor terminal and outdoor main PCB terminal are connected. – Secure that cable in not streched, tensioned or damaged. If the error is not cleared, check according to steps as below. 2. Sensor fault: – Disconnect the sensor from the outdoor main PCB and measure the resistance of the sensor with a multi-meter. – If there is no resistance or the resistance is infinite, it means that the sensor is damaged and shall be replaced. 3. Outdoor main PCB fault (if specific sensor is connected to outdoor PCB) – Disconnect the sensor from the outdoor main PCB and re-wire a spare sensor – Observe whether the error on the control panel is cleared. – If the error is not cleared, the outdoor main PCB is damaged and needs to be replaced. |
| F05 | Low pressure sensor failure – Ps | Failure code shown on indoor unit display. Failure signal comes from outdoor unit. Plausible cause: Lack of refrigerant, wiring, faulty component | When the outdoor main PCB detects that the low pressure sensor is disconnected or out of range, the unit reports a fault and shuts down; | 1. Check refrigerant amount. 2. Poor connection: – Find the connector of the specific sensor according to the wiring diagram. – Secure that the sensor terminal and outdoor main PCB terminal are connected. – Secure that cable in not stretched, tensioned or damaged. 3. Sensor cable damage: – Disconnect the cable from the sensor and main PCB and measure with an Ohm meter if the cable is ok. – Replace cable if broken – If the cable is ok, replace the pressure sensor. 4. If none of the above helps the outdoor main PCB is damaged and need to be replaced. |
| F06 | High pressure sensor failure – Pd | Failure code shown on indoor unit display. Failure signal comes from outdoor unit. Plausible cause: Wiring, faulty component | When the outdoor main PCB detects that the high pressure sensor is disconnected, the unit reports a fault and shuts down; | 1. Poor connection: – Find the connector of the specific sensor according to the wiring diagram. – Secure that the sensor terminal and outdoor main PCB terminal are connected. – Secure that cable in not stretched, tensioned or damaged. 2. Sensor cable damage: – Disconnect the cable from the sensor and main PCB and measure with an Ohm meter if the cable is ok. – Replace cable if broken – If the cable is ok, replace the pressure sensor. 3. If none of the above helps the outdoor main PCB is damaged and need to be replaced. |
| F07 | High pressure switch failure | Failure code shown on indoor unit display. Failure signal comes from outdoor unit. Plausible cause: 3 consecutive P05 alarms within 30 min | When the unit has 3 consecutive high pressure switch protections (P05) within 30 minutes, F07 will be reported and the unit will shut down, and the unit cannot be startup unless re-powered. | Please reffer to actions P05 REMOVE WHEN P05 is checked!!!!!!! 1. When the unit is in standby, if the delta pressure value between the low pressure and the high pressure shows more than 10% in control panel, then measure the gas pressure by pressure gauge (connect the compressor discharge side via high-pressure needle valve, if there are no high-pressure needle valve, connect to the low-pressure needle valve), if there have obvious deviation between the high-pressure sensor detection value and gauge's measurement value, the high pressure sensor need to be replaced. 2. If there is no obvious difference between the value of the low pressure and high pressure , replace the high pressure switch. Note: Replace the high-pressure switch, set the maximum water temperature that the system is allowed to run the unit. Then observe the change of high pressure value during the operation, and observe whether there is still report F08 because of the high pressure protection not timely, and check whether the refrigerant system and the hydro system is abnormal; |
| F08 | Low pressure side pressure switch failure | Outdoor unit | Within 30 minutes, when low-pressure switch protection is reported for three times, then during the third protection, if the indoor unit is not in the second-level antifreeze, the fault is a locked and cannot be restored unless the power is cut off. If the indoor unit is in the second-level antifreeze, without shutdown the unit, the outdoor unit will run at the gear set by the indoor unit, and a failure will be reported. | Accessories and special tools: short wires and main PCB Check if the low pressure is too low according to F11. Since the current unit does not contain a low-pressure switch, this protection generally does not appear. If it does, you can check whether the reserved switch input port is not short-circuited according to the wiring diagram, which causing false alarm; |
| F09 | DC fan motor A failure | Outdoor unit | The unit with only one fan (Capacity ≤ 12kW): If the fan motor startup failed when the outdoor main PCB send fan's running command, the unit will report DC fan A failure, then the unit will shutdown. The unit with 2 fan (Capaciy ≥ 15kW): If the fan motor startup failed when the outdoor main PCB send fan's running command, the unit will report DC fan A failure, then the unit will keep running but compressor frequency will be limited. | Replacement parts and tools: spare fan motor, outdoor main PCB, Multimeter Only single fan units: 1. Confirm that the fan blade is not jammed. 2. Power off the unit, then confirm that the fan blade can turn freely, if not, replace the fan motor. 3. Power off the unit, check whether the terminal are loose or poor contact on the PCB or transfer joint, disconnect the terminal out and install it back in again. 4. Power on and startup the unit, measure the voltage supplied to the DC fan port via multimeter (DC voltage) 4.1. Check the voltage between VCC and GND is 15VDC or not, if the measure value is bigger than 18VDC, replace the outdoor PCB responsible for the fan motor and the fan motor. 4.2. If the voltage of VCC is normal, wire the spare fan motor with the PCB, and start the heat pump to check whether the motor can run normally, if normal, power off the unit and install the motor; if abnormal, replace the PCB. Dual-fan units: 1. Check base on the same 4 steps as above. 2. If one of the two fan is running normally, power off the unit, and wire the two fan ports inversely (fan motor A connect fan B port, fan motor B connect fan A port), then re-power and startup the unit, observe the fan's operation. If the failed fan is still failure, replace its motor. If the otherwise normal fan is not running, replace the PCB. 3. If both two fans do not run, check the voltage of VCC is normal by step 4.1, remove the two failed motor and wire the spare motor to fan A port of the fan motor driver board, power on and startup the unit, observe whether the motor can run normally; then power off again, and wire the spare motor to fan B port, re-power and startup the unit, observe whether the motor can run normally. If the spare motor does not operate on either port, replace the PCB responsible for the Fan motor. If the spare motor operate normally on both ports, re-install the fan motor A, and startup the unit, if the fan A does not operate, fan motor A is damaged; Then remove the fan motor A, and re-install the fan motor B, startup the unit, if the fan B does not operate, fan motor B is damaged, the damaged fan motor should be replaced. |
| F10 | DC fan motor B failure | Outdoor unit | The unit with only one fan (Capacity ≤ 12kW): If the fan motor startup failed when the outdoor main PCB send fan's running command, the unit will report DC fan A failure, then the unit will shutdown. The unit with 2 fan (Capaciy ≥ 15kW): If the fan motor startup failed when the outdoor main PCB send fan's running command, the unit will report DC fan A failure, then the unit will keep running but compressor frequency will be limited. | Replacement parts and tools: spare fan motor, outdoor main PCB, Multimeter Only single fan units: 1. Confirm that the fan blade is not jammed. 2. Power off the unit, then confirm that the fan blade can turn freely, if not, replace the fan motor. 3. Power off the unit, check whether the terminal are loose or poor contact on the PCB or transfer joint, disconnect the terminal out and install it back in again. 4. Power on and startup the unit, measure the voltage supplied to the DC fan port via multimeter (DC voltage) 4.1. Check the voltage between VCC and GND is 15VDC or not, if the measure value is bigger than 18VDC, replace the outdoor PCB responsible for the fan motor and the fan motor. 4.2. If the voltage of VCC is normal, wire the spare fan motor with the PCB, and start the heat pump to check whether the motor can run normally, if normal, power off the unit and install the motor; if abnormal, replace the PCB. Dual-fan units: 1. Check base on the same 4 steps as above. 2. If one of the two fan is running normally, power off the unit, and wire the two fan ports inversely (fan motor A connect fan B port, fan motor B connect fan A port), then re-power and startup the unit, observe the fan's operation. If the failed fan is still failure, replace its motor. If the otherwise normal fan is not running, replace the PCB. 3. If both two fans do not run, check the voltage of VCC is normal by step 4.1, remove the two failed motor and wire the spare motor to fan A port of the fan motor driver board, power on and startup the unit, observe whether the motor can run normally; then power off again, and wire the spare motor to fan B port, re-power and startup the unit, observe whether the motor can run normally. If the spare motor does not operate on either port, replace the PCB responsible for the Fan motor. If the spare motor operate normally on both ports, re-install the fan motor A, and startup the unit, if the fan A does not operate, fan motor A is damaged; Then remove the fan motor A, and re-install the fan motor B, startup the unit, if the fan B does not operate, fan motor B is damaged, the damaged fan motor should be replaced. |
| F11 | Low pressure failure (detected by Ps) | Outdoor unit | Low pressure protection happens three times within 30min (Unit recovers automatically in first two times and no failure displayed). Unit stops and failure can only be cleared by repowering. | Accessories and tools: refrigerant, leakage detector, pressure gauge, vacuum pump 1. When unit is off, read refrigerant pressure value from display (unit standby >30min) for first judgement if serious leakage happens. If saturation temperature corresponding to the displayed refrigerant pressure is at same level of outdoor temperature, it is OK. If it is lower than outdoor temperature for more than 5℃, could be an indicator for refrigerant leakage. 2. For split units, check whether the refrigerant piping exceeds specified length and the refrigerant has not been replenished; if so, replenish the refrigerant according to the length of the piping; 3. Start the unit and observe the change of low pressure. If the low pressure is too low (i.e., the evaporating temperature is lower than the outdoor temperature by more than 10 degrees), and the running time is more than 5 minutes, it can be preliminarily judged as a potential leakage. Fill about 100 to 200g to see whether the low pressure of the system is increased. If yes, proceed leakage test on the system. After finding leakage point and fixing it, vacuum the heat pump system. Then recharge the unit with correct amount of refrigerant based on info from nameplate. |
| F12 | High pressure failure (detected by Pd) | Outdoor unit | If High pressure protection P06 happens three times within 30min, unit stops and failure can only be cleared by repowering. | Accessories and tools: descaling equipment Note: On the display, check data records of the last three reports of high-pressure protection in the failure history. Confirm the temperature difference between the inlet and outlet water temperature (TUO and TUI) and the outlet water temperature (TUO) value at the time of failure happened. Then restart the unit by powering to have it run again, and make the following judgments during the operation process: 1. High pressure too high problem in heating mode: 1.1. Insufficient water flow: Check whether the temperature difference between the inlet and outlet water temperature (TUO and TUI) of the unit is between 3 and 5°C. If it is far more than 5 degrees (e.g., more than 8 degrees) and the system operated normally before, check the filters in the water system to see if there is any dirty blockage and clean them. If it is a newly-installed system, check whether the pump is set to run at low speed, and try to run the pump at a medium or high speed to ensure that the water flow is in a normal range. Ensure that system is done with air purge properly. Check whether the water pressure of the system is below 2.0 bar and whether there is any abnormality in the water system that leads to excessive water resistance of the system; 1.2. Sensor reading deviation: Check the temperature difference between the unit's water outlet temperature (TUO) and the TC temperature or TW temperature. Under normal circumstances, the water outlet temperature (TUO) will be 3 to 5 degrees higher than the TC or TW. If it exceeds 5 degrees, please check whether the TC and TW sensors are not well in position or the installation position is not suitable. TC or TW should be installed in the upper part of the tank; 1.3. Plate heat exchanger scaling: In the process of unit operation, observe whether the temperature of the indoor coil (TUP) is more than 5 degrees higher than the water outlet temperature (TUO). If so, there can be scaling in the plate exchange, cleaning will be needed to remove the scale if so; 2. Cooling mode with high pressure problem: Check whether the evaporator of the outdoor unit is dirty and blocked or there is poor heat dissipation around the external unit. If so, consider adding a wind guide ring to the unit, so that the hot air can be discharged in a timely manner; 3. If the above solution fails to solve the problem, the electronic expansion valve of the refrigerant system may be abnormal. Please refer to "Electronic Expansion Valve detecion". |
| F16 | Water outlet temp. sensor failure TUO | Outdoor unit | When display detects that the water outlet temperature sensor is disconnected or shorted, it will report a failure but unit will not be shut down. Unit keeps working with water inlet temperauter + stop delta T as target temperature. If both the water inlet and outlet water temperature fails, it will be shut down; | Accessories and tools: sensors. electronic control board. multimeter Note: For split unit, indoor control board and water outlet temperature sensor are in indoor unit For monoblock unit, indoor control board is in indoor unit and water outlet temperature sensor is in outdoor unit. 1. Poor contact: Based on unit wiring diagram, find the connection of the temperature sensor. Check contact between sensor terminals and PCB terminals if it is poor. If yes, pull the sensor out and plug it back in. If the fault is cleared, pull the sensor leads toward the electrical box to ensure that there is no tension between the sensor terminals and PCB terminals. If the fault is not cleared, then check according to point 2; 2. Main control board problem: Pull the sensor out from control board and reinsert a new sensor to see whether the failure on display is cleared or not. If the fault is not cleared, it means that the main control board is damaged. Please replace the main control board. If it is cleared, then check according to point 3； 3. Sensor problem： 3.1. For split unit, pull sensor out from control board and use multimeter to detect resistance of sensor. If the resistance value is infinite or no resistance value, then replace the sensor. 3.2. For monoblock unit, check according to 3.1. While for unit with an intermediate connection cable (and the indoor panel is not inside the outside unit), the status of the intermediate connection cable should also be checked; |
| F17 | Water inlet temp. sensor failure TUI | Outdoor unit | When display detects that the water inlet temperature sensor is disconnected or shorted, it will report a failure but unit will not be shut down. Unit keeps working with water inlet temperauter + stop delta T as target temperature. If both the water inlet and outlet water temperature fails, it will be shut down; | Accessories and tools: sensors. electronic control board. multimeter Note: For split unit, indoor control board and water outlet temperature sensor are in indoor unit For monoblock unit, indoor control board is in indoor unit and water outlet temperature sensor is in outdoor unit. 1. Poor contact: Based on unit wiring diagram, find the connection of the temperature sensor. Check contact between sensor terminals and PCB terminals if it is poor. If yes, pull the sensor out and plug it back in. If the fault is cleared, pull the sensor leads toward the electrical box to ensure that there is no tension between the sensor terminals and PCB terminals. If the fault is not cleared, then check according to point 2; 2. Main control board problem: Pull the sensor out from control board and reinsert a new sensor to see whether the failure on display is cleared or not. If the fault is not cleared, it means that the main control board is damaged. Please replace the main control board. If it is cleared, then check according to point 3； 3. Sensor problem： 3.1. For split unit, pull sensor out from control board and use multimeter to detect resistance of sensor. If the resistance value is infinite or no resistance value, then replace the sensor. 3.2. For monoblock unit, check according to 3.1. While for unit with an intermediate connection cable (and the indoor panel is not inside the outside unit), the status of the intermediate connection cable should also be checked; |
| F18 | Indoor coil temp. sensor failure | Outdoor unit | When cooling mode is active, if the indoor coil temperature sensor is detected to be disconnected or shorted, the unit will report a fault and be shut down. When heating mode or hot water mode is active,failure remains but unit will continue to run for heating or hot water; | Accessories and tools: sensors. electronic control board. multimeter Note: For split unit, indoor control board and water outlet temperature sensor are in indoor unit For monoblock unit, indoor control board is in indoor unit and water outlet temperature sensor is in outdoor unit. 1. Poor contact: Based on unit wiring diagram, find the connection of the temperature sensor. Check contact between sensor terminals and PCB terminals if it is poor. If yes, pull the sensor out and plug it back in. If the fault is cleared, pull the sensor leads toward the electrical box to ensure that there is no tension between the sensor terminals and PCB terminals. If the fault is not cleared, then check according to point 2; 2. Main control board problem: Pull the sensor out from control board and reinsert a new sensor to see whether the failure on display is cleared or not. If the fault is not cleared, it means that the main control board is damaged. Please replace the main control board. If it is cleared, then check according to point 3； 3. Sensor problem： 3.1. For split unit, pull sensor out from control board and use multimeter to detect resistance of sensor. If the resistance value is infinite or no resistance value, then replace the sensor. 3.2. For monoblock unit, check according to 3.1. While for unit with an intermediate connection cable (and the indoor panel is not inside the outside unit), the status of the intermediate connection cable should also be checked; |
| F19 | Water flow sensor failure | Outdoor unit | When the water flow sensor is installed on the outdoor main PCB, if there is no feedback signal is detected from the water flow sensor, it means the water flow sensor is failure, the unit will report a fault and be shut down. | Accessories and special tools: water flow sensor. main PCB. multimeter 1. Check whether the water flow sensor connectin cable of the outdoor unit is loose or disconnected, find out the water flow sensor terminal according to the wiring diagram, pull it out and then plug it back in again, if the failure can't be cleared, carry to step 2. 2. When the P0 water pump is running, use a multimeter (DC voltage gear), test the voltage of the water flow port, whether the voltage between GND port and 12V port is 12V, and whether the voltage between GND port and PS3 port is ＞0. If the voltage is ＞0, replace the outdoor main PCB, if the voltage is =0, replace the water flow sensor; 3. When the pump is running，check if the the value of water flow is close to or less than the minimum allowable flow rate of the unit.If so,refer to failure code S02: water flow switch protection, to find out the reason of insufficient of water flow in the system and then solve the problem. |
| F20 | Refrigerant leakage failure | Outdoor unit | When equipped with refrigerant leakage detection function, if refrigerant leakage is detected, after 3 times reported the P16 , F20 will then be reported, at this time, the unit will be locked up and cannot be recovered until repower; | Accessories and tools: refrigerant leakage detector. main PCB. multimeter. USB disk 1. When unit is in Off state, check the refrigerant pressure value in standby state through operation panel(standby time should more than 30 minutes),to confirm whether there is a serious leakage of refrigerant firs.The judgment: whether the saturation temperature that corresponding to the current displayed refrigerant pressure value is the same as the outdoor temperature, and if the refrigerant pressure value is lower than the outdoor temperature by more than 5 ℃, then can judge that there is a leakage of refrigerant basically; 2. Check whether the refrigerant system have leakage problem, use refrigerant leakage detector, check inside the compressor cabinet, check if the refrigerant detection box have leakage alarming, if so, can double check where the leakage point is, if not, carry out the check in step 3; 3. Replace the refrigerant detector(sensor), and then repower the unit, to analyze the way according to step 4; 4. Observe the change of low pressure, if the low pressure is too low (i.e. the evaporating temperature is lower than the outdoor temperature by more than 10 ℃), and the operation time of the unit is more than 5 minutes, it can judge there is a leakage point. Can temporarily supplemented with 100-200g refrigerant to see if the low pressure will have rebound, if so, re-vacuum the unit and re-inject the refrigerant according to the refrigerant amount on the nameplate; |
| N/A | Preserve | Outdoor unit | Preserve | Preserve |
| N/A | Preserve | Outdoor unit | Preserve | Preserve |
| N/A | Preserve | Outdoor unit | Preserve | Preserve |
| N/A | Preserve | Outdoor unit | Preserve | Preserve |
| N/A | Preserve | Outdoor unit | Preserve | Preserve |
| N/A | Preserve | Outdoor unit | Preserve | Preserve |
| Not displayed | Low pressure protection | Outdoor unit | Three minutes after compressor start, if the low-pressure value is less than EEPROM protection value for 20 seconds continuously, then the low pressure protection will be reported and unit will STOP. When entering defrost or within 2 minutes after defrosting, low pressure protection will be detected. | 1. Check whether the outdoor temperature is too low. 2. Check the refrigerant pressure value during standby (min standby time must be 30 min), and initially confirm whether there is a serious leakage of the refrigerant amount. The judgment method is: Check whether the saturation temperature corresponding to the currently displayed pressure value is the same as the outdoor temperature. If it is more than 5 degrees lower than the outdoor temperature, it can be a sign that the refrigerant is leaking. 3. Power on the unit and observe the changes in low-pressure. If the low-pressure is too low (that is, the evaporating temperature is more than 10 degrees lower than the outdoor temperature), and the running time is more than 5 minutes, it can be sign that there is a refrigerant leakage. 100 to 200g of regrigerant can be temporarily added, and see if the system low pressure rises. If so, vacuum the unit again and refill the refrigerant according to the refrigerant amount on the nameplate; 4. If there was severe frosting or unclean defrosting before the unit failure, you can refer to the defrosting failure troubleshooting method. 5. If the above troubleshooting fails to solve the problem, it may be caused by an abnormality in the electronic expansion valve of the refrigerant system. Please refer to the "Troubleshooting – EEV" |
| P01 | Over current Protection | Outdoor unit | When the unit detects that the input current is higher than the value set by the Eeprom of the outdoor unit, the unit will report a fault and shutdown for protection. | Accessories and special tools: Multimeter This protection is generally caused by excessive system load. You can power on again and observe the operation of the unit: 1. If the temperature difference between the inlet and outlet water is greater than 8 degrees during operation, check whether the water pump speed is set to high speed (if it is low speed, please adjust to medium speed or high speed), and also check whether the filter in the water system is blocked; 2. If it is triggered in the sanitary hot water mode (DHW), check whether the domestic water tank coil is too small (the minimum heat exchange area is 0,125㎡ / KWnominal). If it is too small, it may lead to low heat exchange capacity, so heat will continue to accumulate, and eventually due to the water temperature rising too fast also the current rises. 3. During operation, observe the difference between the condenser coil temperature (TUP) and the outlet water temperature (TUO). Normally, the condenser coil temperature (TUP) is 1 to 2 degrees lower than the outlet water temperature (TUO). If TUP is higher than TUO, it may because the heat pump is unable to exchange heat, due to fouling of the plate heat changer (condenser). So the current rises and causes a fault, so as long as the plate changer is descaled and cleaned, the problem can be solved; Clean the plate heat exchanger (condenser). 4.I n cooling mode this fault can be caused by reduced air flow on the evaporator – dirty evaporator, obstacles in front or behind evaporator, faulty fan motor, broken fan blades… 5. False EEPROM settings – upload new EEPROM for the outdoor unit. 6. Check whether the input voltage is normal. If it is lower than the rated voltage by more than 10%, the overcurrent protection may be triggered. Fix the power supplier to adjust the power supply voltage. |
| P02 | Compressor phase current overload protection | Outdoor unit | When the compressor driver PCB detects that the compressor phase current exceeds the compressor phase protection current value, the unit will report a fault and shutdown. | Accessories and special tools: Multimeter This protection is generally caused by excessive system load. You can power on again and observe the operation of the unit: 1. If the temperature difference between the inlet and outlet water is greater than 8 degrees during operation, check whether the water pump speed is set to high speed (if it is low speed, please adjust to medium speed or high speed), and also check whether the filter in the water system is blocked; 2. If it is triggered in the sanitary hot water mode (DHW), check whether the domestic water tank coil is too small (the minimum heat exchange area is 0,125㎡ / KWnominal). If it is too small, it may lead to low heat exchange capacity, so heat will continue to accumulate, and eventually due to the water temperature rising too fast also the current rises. 3. During operation, observe the difference between the condenser coil temperature (TUP) and the outlet water temperature (TUO). Normally, the condenser coil temperature (TUP) is 1 to 2 degrees lower than the outlet water temperature (TUO). If TUP is higher than TUO, it may because the heat pump is unable to exchange heat, due to fouling of the plate heat changer (condenser). So the current rises and causes a fault, so as long as the plate changer is descaled and cleaned, the problem can be solved; Clean the plate heat exchanger (condenser). 4. In cooling mode this fault can be caused by reduced air flow on the evaporator – dirty evaporator, obstacles in front or behind evaporator, faulty fan motor, broken fan blades… 5. False EEPROM settings – upload new EEPROM for the outdoor unit. 6. Check whether the input voltage is normal. If it is lower than the rated voltage by more than 10%, the overcurrent protection may be triggered. Fix the power supplier to adjust the power supply voltage. |
| P03 | IPM module protection | Outdoor unit | During compressor operation, the compressor driver PCB is detected to be overheating (the protection value is generally 95-100 degrees) or over-current protected, and the unit reports a fault and shutdown; | Accessories and special tools: clamp flow meter. Multimeter 1. Refer to the P02 troubleshooting method 2. In cooling mode, please check whether the fan is running normally (whether the speed is low, such as below 500 rpm) or only one fan is running in the dual fan system, if yes please refer to the handling of fan failure, check and replace the motor if needed. 3. In cooling mode this fault can be caused by reduced air flow on the evaporator – dirty evaporator, obstacles in front or behind evaporator, faulty fan motor, broken fan blades… 4. Exchange for compressor driver PCB |
| P04 | Compressor oil return protection | Outdoor unit | Running low frequency below F3 for more than 20 minutes will trigger the Oil return function which will speed up the compressor speed for a short period to make sure the oil circulates back to the compressor. When function finished, the compressor speed will be adjusted accordingly to the normal state. This is normal protection and does not require any treatment. | This is normal protection function and does not require any treatment. |
| P05 | High pressure switch protection | Outdoor unit | Fault shutdown is reported when a high pressure switch port disconnection is detected for 5 seconds after the compressor has been started for 1 minute | Accessories and specialized tools:/ 1. Please check error history to see if the high pressure value is higher than 42 Bar when unit report this error; if so, please check the value of high pressure sensor (please refer to High Pressure Sensor Failure section for description). If the latest high pressure protection value was less than 41 bar, then the high pressure switch may failed, pls replace high pressure switch. 2. Check if there is insufficient heat dissipation on the high-pressure side (condensing side) Data recording, after confirming the temperature difference between the inlet and outlet water, shut down and repower the unit. Then the following judgments are made: 2.1. Confirm that the temperature difference between the water inlet and outlet is within 5 degrees, if it exceeds 8 degrees, please check whether the water pump is set to low speed, if yes please try to let the water pump run at medium or high speed, to ensure that the water flow is within the normal range; Also check the filters in the water system, whether there is a dirty blockage, and if needed, clean it; 2.2. Confirm the temperature difference between the outlet water temperature and the TC temperature or TW temperature. Normally, the outlet water temperature will be 3 to 5 degrees higher than the TC or TW, if it is more than 5 degrees, please check whether the installation position of the TC and TW sensors is installed in an inappropriate position, the TC or TW should be installed in the middle and upper part of the water tank; 2.3. During the operation of the unit, observe whether the temperature of the condenser coil (TUP) is higher than the temperature of the outlet water (TUO). If the temperature of the condenser coil (TUP) is higher than the temperature of the outlet water by more than 3 degrees, check if there is fouling of the plate heat exchanger (condenser). As long as the plate heat exchanger (condenser) is descaled and cleaned, the problem can be solved; 2.4. In cooling mode this fault can be caused by reduced air flow on the evaporator – dirty evaporator, obstacles in front or behind evaporator, faulty fan motor, broken fan blades… 3. If all of above solutions can not solve the problem, the EEV may be abnormal, please refer to the "Electronic Expansion Valve Investigation Part". |
| P06 | High pressure overpressure protection | Outdoor unit | If the high pressure detected by the high pressure sensor Pd is higher than the system pressure protection value after the compressor has been running for 1 minute, the unit will report faulty shutdown protection; | Accessories and specialized tools:/ 1. Determine if there is insufficient heat dissipation on the high-pressure side (condensing side). After recording the data and confirming the temperature difference between the inlet and outlet water (TUO and TUI) and the outlet water temperature at the time of the unit's protection shutdown, power down and restart the unit to allow the unit to run again, and make the following judgments during the operation process: 1.1. Confirm that the temperature difference between the inlet and outlet water (TUO and TUI) of the unit is within 5 degrees, if it exceeds 8 degrees, please check whether the water pump (P0) is set to low speed, and try to let the water pump run at medium or high speed to ensure that the water flow is within the normal range; check the filters in the water system, whether there is a dirty blockage, and if needed clean it; 1.2. Confirm the temperature difference between the outlet water temperature (TUO) of the unit and the TC temperature or TW temperature, under normal circumstances, the outlet water temperature (TUO) will be 3 to 5 degrees higher than the TC or TW, if it is more than 5 degrees, please check whether the installation position of the TC and TW sensors is checked off or installed in an inappropriate position, the TC or TW should be installed in the middle and upper part of the water tank as far as possible; 1.3. During the operation of the unit, observe whether the temperature of the condenser coil (TUP) is higher than the temperature of the outlet water (TUO). If the temperature of the condenser coil (TUP) is higher than the temperature of the outlet water (TUO) by more than 3 degrees, there is scaling in the plate exchange, and it is necessary to clean the water side of the plate exchange to remove the scale; 1.4. If it occurs in cooling mode, check for poor ventilation around the unit, check the evaporator of the outdoor unit for dirt and blockage, and clean debris from the outdoor heat exchanger (evaporator); Check for poor ventilation around the outside unit, compare the outdoor temperature sensor display and the measured outdoor temperature on site to see if there is a big difference, if the difference between the two is big, check the Outdoro temperature sensor. 2. If the above troubleshooting is unable to solve the problem, the electronic expansion valve of the refrigerant system may be abnormal, please refer to the "Electronic Expansion Valve Investigation Part". |
| P07 | Compressor oil preheat function. Initial power-up preheat protection | Outdoor unit | When the unit is powered on, if the outdoor temperature is lower than -5 degrees, the unit will warm up the compressor oil for 30 minutes before start of the compressor.System will use a electric heater (crankcase heater) on the bottom part of the compressor, to heat up the compressor oil. | This is normal protection function and does not require any treatment. |
| P08 | High discharge temperature protection Detected by temp. sensor Td | Outdoor unit | When the discharge temperature (Td) is higher than the value of protection shutdown point during unit operation, compressor stop. | Accessories and special tools: discharge temperature sensor (Td), refrigerant, refrigerant leak detector, pressure gauges. electronic scale, multimeter 1. Examine the factors of insufficient refrigerant: 1.1. Under the standby mode (in stand-by for min 30 mins), check the refrigerant pressure value, and confirm whether there is serious leakage of refrigerant quantity initially. The judgment way is: whether the saturation temperature corresponding to the pressure value currently displayed, is the same as the outdoor temperature, and if it is lower than the outdoor temperature by more than 5 degrees, it can be judged that there is a leakage of refrigerant basically; 1.2. For split units, check whether the refrigerant piping exceeds the max refrigerant piping lengths or if refrigerant was not added based on the longer piping as factory prefiiling; if so, add refrigerant according to the length of the piping; 1.3. Start the heat pump, make sure that the evaporator is clean, and observe the change of low pressure, if the low pressure is too low (i.e. the evaporating temperature is lower than the outdoor temperature by more than 10K), and the running time is more than 5 minutes, you can initially judge that it is suspected that the refrigerant is leaking, and you can temporarily add approx. 100-200g of refrigerant to see whether the low pressure of the system is rising or not. And whether the discharge temperature is dropping. If so, there is a leakage point in the unit, repair the leakage and fill the unit with new refrigerant. Re-evacuate the unit and refill the refrigerant according to the refrigerant quantity on the nameplate; 2. Examine the factors of insufficient heat transfer Please check the error history, if there is no high pressure protection, the effect of poor heat exchange can be ruled out. 3. Sensor problem: Disconnect the temp. sensor (Td) from the Main outdoor PCB, and use a multimeter to measure the resistance of the Td temp. sensor, and compare it with the NTC50kOhm temp. sensor resistance table. If there is a large deviation, then replace the discharge temperature sensor; 4. If the above troubleshooting fails to solve the problem, the electronic expansion valve of the refrigerant system may be abnormal, please refer to "Electronic Expansion Valve Troubleshooting Part". |
| P09 | Evaporator coil over-temperature protection Detected by temp. sensor Tp | Outdoor unit | In the cooling mode, the evaporator coil temperature (Tp) is higher than the evaporator coil over-temperature protection value (62 degrees), then the unit reports a fault and shutdown; | Accessories and Specialized Tools: Motors 1. In cooling mode, please confirm whether the fan motor is running normally (whether the speed is low, such as less than 500 rpm) or only one fan is running in the dual fan system. If yes, please refer to the solution of fan motor failure, investigate and replace the motor. 2. In cooling mode, you can check whether the evaporator is dirty or blocked or the heat island effect is caused by the installation position, resulting in high current. You can clean the evaporator, adjust the installation location, or install an discharge duct to eliminate the heat island effect; |
| P10 | Input voltage over-under-voltage protection (only for single-phase units) | Outdoor unit | When the unit is with power supply (either running or standby) and the input voltage is detected to be lower than 140V or higher than 270V, the unit will report a fault and shutdown; | Accessories and special tools: main PCB, fan motor, multimeter 1.1. Using a multimeter, measure whether the voltage between L and N line is normal nor not, and the voltage range of the single phase unit should be in the range of 140V-270V. 2. Disconnect the power, unplug the DC fan from the PCB, and then re-power to confirm whether the voltage detection abnormality is caused by the damage of the motor. If the fault is cleared, then replace the DC fan, if the fault is not cleared, then replace the main PCB; |
| P11 | Outdoor temperature out of range shutdown protection. Detected by temp. sensor Ta | Outdoor unit | Heating mode: when the outdoor temperature is lower than -25°C, or the outdoor temperature is higher than 45°C, the unit will stop the compressor; Cooling mode: when the outdoor temperature is lower than 8 degrees, or the outdoor temperature is higher than 65 degrees, the unit will report a fault and shutdown; | If the temperature sensor would make false reading: Accessories and special tools: outdoor temperature sensor, multimeter 1. Through the multimeter, test if the outdoor temperature sensor resistance value corresponding to temperature resistance table, if there is a deviation, then replace the sensor 2. Confirm whether the current actual outdoor temperature reaches the limitation point of heat pump outdoor temperature. If so, please wait for the outdoor temperature reach to a normal range, and the unit will back to normal; 3. Check whether the installation position of the ambient sensor is blocked by ice or exposed to direct sunlight, if so, please protect the outdoor temperature sensor, to prevent icing or exposure to direct sunlight; 4. Check whether there is any heat island effect (cold island effect) in the installation position of the unit, and adjust the installation position or install an discharge duct to eliminate the heat island or cold island effect; |
| P12 | Outdoor temperature compressor limitation | Outdoor unit | The unit is following the envelope of the compressor running conditions. At certain outdoor temperatures the max compressor speed is automatically limited. This is a normal protection function, which is signaled form the OU to the IU controller as Info. | This error will not show in display, but if target water temperature have a big difference with real water temperature, and unit could not run in high speed, you can consider if it because the outdoor temperature is too high, so frequency is limited. You can confirm the accuracy of the outdoor temperature check according to the troubleshooting of P11; |
| P13 | Low pressure switch protection | Outdoor unit | When the unit has been up and running for 3 minutes, if a low voltage switch disconnection is detected, a fault is reported; | Accessories and specialized tools: short cables, main PCB According to F11 low pressure checking this error, since the unit does not have low pressure switch, this protection does not normally occur. If it does, follow the wiring diagram to check whether the reserved input port has not been shorted, resulting in a false alarm; |
