Hitachi Yutaki M & Yutaki S fault 3
Abnormal transmission between outdoor and indoor units
Heat pumpWhat it means
Transmission fault category; communication failure between outdoor and indoor units.
Likely causes
- Loose, disconnected, broken or short-circuited connector
- Incorrect wiring
- Failure of PCB
- Tripping of fuse
- Power supply OFF
Where to start
- Check connector condition between indoor and outdoor unit communication line
- Check LED1 (Red) on PCB1 for Power status
- Check LED2 (Green) on PCB1 for Communication with inverter status
The full answer, free
- 7 more checks in order
- How to put it right, step by step
- The manual page for this fault (page 337), right under the answer
Safety: Isolate the outdoor unit and any backup heater, and give the inverter capacitors time to discharge before you open the electrics. Anything on the refrigerant circuit needs F-gas certification.
From the Hitachi manual for the Yutaki M & Yutaki S. Check the model on the data plate before you order parts.
Other Hitachi Yutaki M & Yutaki S fault codes
- 03Lost communication with all sub YUTAKI units
- 10Indoor 2nd DHW thermistor anomaly
- 100Indoor-LCD compressor protection
- 106Excessively high discharge gas temperature
- 12Indoor water outlet thermistor abnormally (THMwo)
- 15Water circuit 2 thermistor abnormally (THMwo2)
- 16Water DHW thermistor abnormally (THMdhwt)
- 17Auxiliary sensor 2 thermistor abnormally (THMaux2)
- 18Auxiliary sensor 1 thermistor abnormally (THMaux1)
- 19Activation of the protection device for the indoor fan motor
- 2Activation of protection device (high pressure cut)
- 203Sub PC-ARFH2E stops answering to main PC-ARFH2E
- 204Indoor unit stops answering to main PC-ARFH2E
- 209Sub DHW configured on unexisting module
- 21XModule X is in alarm state (sub unit)
- 22Thermistor for outdoor ambient temperature (THM7)
- 25Auxiliary sensor 3 thermistor abnormally (THMaux3)
- 31Incorrect capacity setting or combined capacity between outdoor and indoor units
- 35Incorrect indoor unit number setting
- 38Abnormality of picking up circuit for protection (outdoor unit)
- 4Abnormal transmission between inverter PCB and RASC unit PCB
- 40Incorrect LCD setting
- 48Activation of overcurrent protection
- 5Reception of abnormal operation code for detection of power source phase