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Causes and determination of faults in Carel DC Inverter Heat Pump

Views: 3957     Author: Site Editor     Publish Time: 2023-03-28      Origin: Site

Causes and determination of faults in Carel DC Inverter Heat Pump
Error Code Description Possible Causes Measure to Judge Solution
AL001 AL001 Too many mem writings Frequent parameter changes
Frequent parameter changes
Stop operating the controller or power off for 3 minutes
AL002 AL002 Retain mem write error Frequent parameter changes Frequent parameter changes Stop operating the controller or power off for 3 minutes
AL003 AL003 Inlet probe error Loose wire/Wire break/Broken probe Visual inspection Connect the wires tightly/ Reconnect the wire/ Replace the probe
AL004 AL004 Outlet probe error Loose wire/Wire break/Broken probe Visual inspection Connect the wires tightly/ Reconnect the wire/ Replace the probe
AL005 AL005 Ambient probe error Loose wire/Wire break/Broken probe Visual inspection Connect the wires tightly/ Reconnect the wire/ Replace the probe
AL006 AL006 Condenser coil temp Loose wire/Wire break/Broken probe Visual inspection Connect the wires tightly/ Reconnect the wire/ Replace the probe
AL007/AL137 AL007 Water flow switch Clogged filter, resulting in low flow rate
Low water flow Clean filters
Air in pipes causing poor water flow Low water flow Evacuate pipeline and install automatic venting valve at the highest point of the system
 Water pump is not emptied, resulting in low flow Low water flow Empty the water pump
Water system with valves closed or not fully open Low water flow Open the valve
Water pump is too small, resulting in low flow Low water flow Replace the  water pump with a higher head flow rate
Water flow switch is broken If the above are ruled out, you can short the water flow switch and force the machine on. If the water outlet temperature is greater than the tank temperature of 8 degrees or more, continue the above operation. Within 5 degrees and no fault in the start-up, the water flow switch is broken. Replace the water flow switch
Water pump is broken Water pump does not turn Replace water pumps
AL008 AL008 Phase sequ.prot.alarm Parameter setting exceptions Three-phase unit reports fault Set DI5 on the Ot6 page inside M09 to Normally Open NO
AL013 AL013 Low superheat - Vlv.A Long-term operation of the unit at low frequencies outside its operating range Long-term operation of the unit at a low frequency of 30Hz Change the parameter of Alarm delay in the EEV n 1 page in M07 to 9999
AL028 AL028 Battery discharge EVD Strong electrical interference with the unit Report a fault Power off for 3 minutes and then restart
AL037 AL037 BLDC-alarm:Out of Envelope Water temperature too high or ambient temperature too low Ambient or water temperature outside the permitted range of the unit Operates within the permitted operating range
AL038 AL038 BLDC-alarm:Starting fail wait Program error Check if the program version is up to date Brush up on the latest programsBrush up on the latest programs
AL039 AL039 BLDC-alarm:Starting fail exceeded Program error Check if the program version is up to date Brush up on the latest programsBrush up on the latest programs
AL041/AL050 AL041 BLDC-alarm:High discarge gas temp Lack of refrigerant Low pressure is too low ausing high exhaust Leak check and repair then evacuate and fill with refrigerant according to the nameplate
Exhaust probe not sensing correctly Exhaust probe shows high or low even after shutdown 更换排气探头
AL051/AL057/AL082/
AL051 Power+ alarm:01-Overcurrent Low supply voltage Voltage measured with multimeter in standby, 10% below rated voltage Add a voltage regulator to keep the voltage stable, or provide a stable voltage, or thicken the power cable
Low voltage due to small wire diameter When the compressor is started and the voltage is measured with a multimeter, the voltage will slowly become lower and the voltage shown on the multimeter will be more than 10% below the rated voltage Replace suitable wire diameter
High current due to loose compressor or inverter wiring Check if the power cable, compressor wiring, inverter inlet and outlet cables are loose and if there are burn marks Re-crimpe wire joints
Compressor coils short-circuited Exclude the above, measure the resistance between the three coil columns of the compressor two by two, there is a very small or large resistance, indicating that the compressor is bad Replace Compressor
AL053 AL053 Power+ alarm:03-DCbus overvoltage Excessive voltage Actual voltage exceeds the rated by more than 20% under the measurement Provide stable supply voltage
AL054 AL054 Power+ alarm:04-DCbus undervoltage Voltage too low The actual voltage is more than 25% below the rated voltage at the time of measurement Provide stable supply voltage
AL114 AL114 Power+ alarm:Power+ offline Too short an interval between power-off and power-up of the main unit Re-powering time less than 30 seconds Power off again and power back on after 3 minutes, if still not possible then power off for 10 minutes
Loose inverter connection cable Screws not tightened Retighten
Inverter dipswitch in wrong position The four dip switches of the inverter are not oriented in the same direction Re-dial to Consistency
AL115 AL115 EEV alarm:Low superheat Long-term operation of the unit at low frequencies outside its operating range Long-term operation of the unit at a low frequency of 30Hz Change the parameter of Alarm delay in the EEV n 1 page in M07 to 9999
AL128 AL128 Low press alarm Severe frosting of mainframe fins The fins are covered in a very thick frost Forced defrost, place the ambient probe as far away from the fins as possible to prevent it from being covered by snow and check for abnormal parameters
Insufficient airflow due to bad airfoil Broken wind blades Replace wind blade
Refrigerant leakage from the system The low pressure is too low and oil leaks can be seen in the lines Leak check and repair then evacuate and fill with refrigerant according to the nameplate
Low pressure pressure sensor is broken Low pressure gauge over 1kg, still reporting low pressure alarm Replace low pressure sensor
AL129 AL129 High press alarm Clogged filter, resulting in low flow

Difference in temperature between inlet and outlet water of more than 8 degrees Clean filters
Air in the pipes, causing poor water flow Difference in temperature between inlet and outlet water of more than 8 degrees Evacuate pipeline and install automatic venting valve at the highest point of the system
Water pump not emptied, resulting in low flow Difference in temperature between inlet and outlet water of more than 8 degrees Empty the water pump
Water system with valves closed or not fully open No or low water flow Open the valve
The hot water probe or underfloor heating probe is not placed in the corresponding return pipe or blind pipe of the water tank Very high water discharge temperature, over 60 degrees Place the probe in the corresponding position
Pump head or flow rate too low, resulting in low flow rate Difference in temperature between inlet and outlet water of more than 8 degrees Replace the  water pump with a higher head flow rate
High pressure due to water-side heat exchanger fouling Low temperature difference between inlet and outlet water, high pressure Cleaning of water-side heat exchanger with water treatment
High pressure due to air in the fluorine system Jittering of the high pressure gauge needle Re-vacuumine  and refill with refrigerant
Bad high voltage sensor switch Pressure gauge does not exceed maximum pressure, but still reports high pressure alarm Replace the high-pressure pressure sensor
High pressure due to bad electronic expansion valve Low pressure is too low, and high pressure is too high Replace the electronic expansion valve
AL130 AL130 Disc.temp.probe error Loose wire/Wire break/Broken probe Visual inspection Connect the wires tightly/ Reconnect the wire/ Replace the probe
AL131 AL131 Suct.temp.probe error Loose wire/Wire break/Broken probe Visual inspection Connect the wires tightly/ Reconnect the wire/ Replace the probe
AL134 AL134 Tank temp.probe error Loose wire/Wire break/Broken probe Visual inspection Connect the wires tightly/ Reconnect the wire/ Replace the probe
AL138 AL138 High temp. alarm Clogged filter, resulting in low flow
Water outlet temperature above 62 degrees Clean filters
Air in the pipes, causing poor water flow Water outlet temperature above 62 degrees Evacuate pipeline and install automatic venting valve at the highest point of the system
Water pump not emptied, resulting in low flow Water outlet temperature above 62 degrees Empty the water pump
Water system with valves not fully open Water outlet temperature above 62 degrees Open the valve
Set temperature too high and flow rate too low Water outlet temperature above 62 degrees Reduce the setting temperature
Water pump too small, resulting in low flow Water outlet temperature above 62 degrees Replace the  water pump with a higher head flow rate
AL139 AL139 Low temp. alarm Clogged filter, resulting in low flow
Water outlet temperature below 5 degrees Clean filters
Air in the pipes, causing poor water flow Water outlet temperature below 5 degrees Evacuate pipeline and install automatic venting valve at the highest point of the system
Water pump not emptied, resulting in low flow Water outlet temperature below 5 degrees Empty the water pump
Water system with valves not fully open Water outlet temperature below 5 degrees Open the valve
Set temperature too high and flow rate too low Water outlet temperature below 5 degrees Reduce the setting temperature
Water pump too small, resulting in low flow Water outlet temperature below 5 degrees Replace the  water pump with a higher head flow rate
AL153/AL154 AL153 Fan1/2 fault Fan drive dipswitch anomaly Visual inspection Fan drive dipswitch to be redialed, top left, bottom right
Loose wind turbine wiring Check that the fan power socket is tightly plugged in Plug the fan connection socket firmly
Bad wind turbine drive Visual inspection of the power light does not illuminate Replace the fan drive
Broken motor Manual rotation of the motor with jamming Replace the motor
AL155 AL155 Fans Offline Fan drive dip switch abnormal Visual inspection Fan drive dipswitch to be redialed, top left, bottom right
Loose wind turbine wiring Check that the fan power socket is tightly plugged in Plug the fan connection socket firmly
Wind turbine drive is broken Visual inspection of the power light does not illuminate Replace the fan drive
Broken motor Manual rotation of the motor with jamming Replace the motor



Abnormal Exclusion

Serial Number Abnormal State Possible Causes Measure to Judge Treatment Measures
1 Unit does not operate The machine is not switched on Visual inspection With hot water or heating symbols it is on
Loose linkage switch Visual inspection Short the linkage switch
The machine is faulty Visual inspection Troubleshooting
2 Difficult to close AC contactors Voltage too low or wire diameter too small Check the voltage with a multimeter and check the wire gauge Add a voltage regulator to keep the voltage stable
3 Water pump running but water not circulating or noisy pump Water system with air Hands-on screening Water system air discharge
Water system valves not fully opened Visual inspection Open the valve
Filters are dirty and clogged Hands-on screening Clean filters
4 The room is not heated High heat dissipation in a room with a lot of glass leads to an undersized machine configuration Visual inspection Increased configuration
The room is slow to heat up with humidity The new house is rather damp Waiting for the room to dry
The room heats up slowly at first
Wait long enough for the room temperature to rise
Wet weather, resulting in frequent frost defrosting
Wait long enough for the room temperature to rise
5 The compressor runs but the unit does not produce heat Refrigerant leaks
Leak check and repair then evacuate and fill with refrigerant according to the nameplate
Compressor damage
Leak check and repair then evacuate and fill with refrigerant according to the nameplate
Stuck four-way valve
Tap on the four-way valve body
6 Defrost is not clean or does not go into defrost Coil probe dislodged
Place the coil probe into the probe clamp
Ambient probe covered in frost
Position the environmental probe on the fins as far away from the fins as possible
M10 inside the defrost ssetting parameters are inaccurate,so the unit can not enter the defrost.  The defrost conditions: 1 coil B9 temperature is lower than the M10 inside the Df04 page set value (default -1 degrees), 2 ambient temperature B3 minus the coil temperature B9 is greater than or equal to the set parameters M10 inside the Df05 page set value (default is 5), 3 ambient temperature B3 is less than or equal to the M10 inside the Df04 page set value (default 15 degrees), 4 defrost interval time reached (default 45 minutes)
Firstly, check the defrost parameter settings. If the parameters are correct, check whether the four entry conditions are met during normal operation of the unit. Then, adjust the parameters that are not met and allow the unit to enter the defrost. After defrosting, then make targeted adjustments.


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Guangzhou SPRSUN New Energy Technology Development Co., Ltd.

A Professional Heat Pump Manufacturer Since 1999
No.15 Tangxi Road, Yinsha lndustrial Park, Xintang, Zengcheng , Guangzhou, Guangdong, China, 511338

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