Joule Modul Air fault 12
No communication with the room thermostat
Heat pumpWhat it means
The heat pump has lost communication with the room thermostat. This is a locking fault requiring installer intervention to override.
Likely causes
- Faulty electrical connection
- Thermostat malfunction
Where to start
- Check electrical connections
- Check the thermostat is operating correctly
The full answer, free
- How to put it right, step by step
- The manual page for this fault (page 105), 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 Joule manual for the Modul Air. Check the model on the data plate before you order parts.
Other Joule Modul Air fault codes
- 13No communication with the boiler
- 20Filter reached end of lifespan
- 30Top tank temperature sensor error
- 31Bottom tank temperature sensor error
- 32Back up heater water heater temperature sensor error
- 71Over-temperature flow protection triggered
- 80No temperature difference across the condenser
- 95Water pressure is critically low (< 0.3 bar)