Fujitsu Heat Pump Troubleshooting

In the tables below you can find the list of possible troubles which you can encounter using your Fujitsu heat pump. The information given there may be helpful in case of your heat pump not working properly.

The types of defects or breakdowns are various. There are detailed descriptions of possible problems and causes of heat pump not cooling or heat pump fan not spinning. Here you can find some questions which give you the idea what to investigate or to check before addressing to the specialists.

The Fujitsu heat pump flash codes given in the tables and their descriptions are meant to give you the key to the possible problems you have with your heat pump. Do not try to do any repair if you are not a specialist!

Fujitsu 112 Heat Pump Troubleshooting

Diode displayError contents
1 FlashSerial forward transfer error.
2 FlashesDischarge thermistor error.
3 FlashesPressure sensor error.
4 FlashesHeat-exchange thermistor (outlet) error.
5 FlashesHeat-exchange thermistor (intermediate) error.
6 FlashesExpansion valve thermistor error.
7 FlashesOutdoor temperature thermistor error.
8 FlashesCompressor thermistor error.
9 FlashesHeat sink thermistor (inverter) error.
10 FlashesHeat sink thermistor (P.F.C.) error.
11 FlashesDischarge temperature protection (permanent stoppage).
12 FlashesCompressor temperature protection (permanent stoppage).
13 FlashesCurrent trip (permanent stoppage).
14 FlashesDetection of compressor position error (permanent stoppage).
15 FlashesCompressor start up error (permanent stoppage).
16 FlashesFan motor (1) error (permanent stoppage).
17 FlashesFan motor (2) error (permanent stoppage).
18 FlashesInverter error.
19 FlashesP.F.C. error.
20 FlashesLow pressure abnormal.
21 FlashesConnection with hydraulic unit error.
22 FlashesHydraulic unit abnormality condition.

Fujitsu Waterstage WOYG112LCTA Heat Pump Troubleshooting

Outdoor unit Error numberLED 2 (green)LED 1 (red)Error contents
111 Flash1 FlashCommunication error between Hydraulic unit and Outdoor unit.
232 Flashs3 FlashsConnection forbidden (series error).
313 Flashs1 FlashIndoor unit power supply abnormal.
322 FlashsSerial communication error between Controller /Interface PCBs.
414 Flashes1 FlashHeat pump capacity signal error (Open or short).
422 FlashesHydraulic unit heat-exchange thermistor Error.
616 Flashs1 FlashOutdoor unit power supply abnormal.
622 FlashsOutdoor unit main PCB error.
633 FlashesInverter error.
644 FlashesActive filter error.
655 FlashsOutdoor unit IPM error.
677 FlashsOutdoor unit power short interruption error (protective operation).
688 FlashsOutdoor unit magnetic relay error.
717 Flashes1 FlashDischarge thermistor error.
722 FlashesCompressor thermistor error.
733 FlashesHeat-exchange thermistor (outlet / intermediate) error.
744 FlashesOutdoor thermistor error.
777 FlashsOutdoor unit heat sink temp, thermistor error.
788 FlashesExpansion valve thermistor error.
848 Flashes4 FlashesCurrent sensor error.
866 FlashesPressure sensor error Z Pressure switch error.
949 Flashes4 FlashesCurrent trip.
955 FlashesDetection of compressor position error Z Compressor start up error.
977 FlashesOutdoor unit fan motor error.
A110 Flashes1 FlashDischarge temperature protection.
A33 FlashesCompressor temperature protection.
A44 FlashsOutdoor unit pressure error.
A55 FlashesLow pressure abnormal.
A99 FlashsCurrent overload error.

Fujitsu AOYA18LALL Heat Pump Troubleshooting

Error numberError descriptionHeat pump operation despite the error
-No connectionNo
10Outdoor sensorYes with OT = 0 °C
33Heat pump initial temperature sensor errorYes
44Heat pump return temperature sensor error
50DHW temperature sensor
60Ambient temperature sensor 1
65Ambient temperature sensor 2
105Maintenance message
121Flow temperature for (HC1) not reached
122Flow temperature for (HC2) not reached
127Anti-legionella temperature not reached
369External fault (safety component)No

Fujitsu WSYA 065 DA Heat Pump Troubleshooting

Diode displayErroneous element
1 FlashTransmission error, "hydraulic module - outside unit"
2 FlashesAbnormal discharge temperature or defective discharge sensor
3 FlashesDefective exchanger sensor
4 FlashesDefective outside temperature sensor
5 FlashesAbnormal compressor temperature or defective compressor temperature sensor
6 FlashesHP pressure switch cut off
7 FlashesAbnormal current quality
8 FlashesCurrent quality detection circuit defective
9 FlashesActive filter error
10 FlashesCompressor is not operating
11 FlashesExternal fan error
12 FlashesCompressor casing resistance fault
13 FlashesActive filter cut off for over-intensity

Fujitsu AOYA30LBTL Heat Pump Troubleshooting

Diode displayErroneous element
0,1 seconds lit and 0,1 seconds unlitDefective temperature sensor (see hydraulic module)
0,5 seconds lit and 0,5 seconds unlitAbnormal intensity detector error
2 seconds lit and 2 seconds unlitElectric current circuit breaker error
5 seconds lit and 5 seconds unlitDefective fan motor
0,1 seconds lit and 2 seconds unlitPosition of the compressor's rotor not detected
5 seconds lit and 0,1 seconds unlitAbnormal PAM circuit voltage
1 seconds lit and 0,1 seconds unlitTimer cut off
2 seconds lit and 5 seconds unlitAbnormal compressor temperature
5 seconds lit and 2 seconds unlitActive filter error
Permanently litAbnormal discharge temperature

Fujitsu AOY54LJBYL Heat Pump Troubleshooting

Diode displayErroneous element
0,1 seconds lit and 0,1 seconds unlitDefective temperature sensor (see hydraulic module)
0,5 seconds lit and 0,5 seconds unlitDefective I PM card
2 seconds lit and 2 seconds unlitCommunication serial bus error (terminals 3 outside unit & hydraulic module)
5 seconds lit and 5 seconds unlitDefective fan motor
0,1 seconds lit and 2 seconds unlitPosition of the compressor's rotor not detected
5 seconds lit and 0,1 seconds unlitDefective ACTPM card
Permanently litAbnormal discharge temperature