| Error code | Possible fault | Installer action | |
|---|---|---|---|
| E09 | Gas valve connection cable | Check the cable PCB/gas valve and gas valve plug. | |
| E10 | External probe fault | Check the sensor. | |
| E12 | Differential water flow switch fault (still open) | Check the water flow switch. | |
| E13 | Differential water flow switch fault (still closed) | Check the water flow switch. | |
| E15 | Gas valve command fault | Check the cable PCB/gas valve, replace PCB if necessary. | |
| E20 | Central heating NTC fault | Check the sensor. | |
| E28 | Flue NTC fault | Check the sensor. | |
| E40 | Central heating return NTC fault | Check the sensor. | |
| E50 | DHW NTC sensor fault (tank boiler) (s.c.) OR DHW NTC sensor fault (tank boiler) (o.c.) | Check the sensor. | |
| E83/E84/E85/E86/E87 | No communication | Check cable between room unit and PCB or RF link. | |
| E109 | Pre-circulation fault | Check the correct circulation of the water and the pump. | |
| E118 | Primary system water pressure too low (< 0.5 bar) | Check the water pressure. | |
| E125 | Circulation fault (primary) | Check the correct circulation of the water and the pump | |
| E128 | Frequent flame failure (12 times) | Check the sensing electrode and the cable, flue recirculation, enable the automatic calibration function before replacing components. | |
| E129 | Safety error for frequently loss of flame with max correction during the ignition during Calibration Function | Check the sensing electrode and the cable, flue recirculation, enable the automatic calibration function before replacing components. | |
| E130 | Flue thermostat sensor tripped (lockout) | Check the thermostat, the correct circulation of the water and the pump. | |
| E133 | Interuption of gas supply or flame failure | Check the power supply, sensing electrode, spark electrode and cable. Check flue recirculation, enable the automatic calibration function before replacing components. | |
| E134 | Elapsed time gas valve open without gas (short request in a short period) | Check the gas pressure, sensing electrode, spark electrode and cable, replace the PCB if necessary. | |
| E135 | Interuption of gas supply (internal error) | Replace PCB. | |
| E154 | Flow/return sensor temperature test Check the correct circulation of the water and the pump, | check the correct position of the sensors. | |
| E160 | Fan or fan wiring fault | Check the fan and the cable. | |
| E163 | Domestic Hot Water NTC sensor fault (s.c.) OR Domestic Hot Water NTC sensor fault (o.c.) | Check the sensor. | |
| E270 | Circulation fault (dry fire) | Check the sensor and the correct circulation of the water and the pump. | |
| E317 | Wrong power supply electrical frequency (Hz) | Check the frequency (Hz) and the power supply. | |
| E321 | Hot water NTC fault | Check the sensor. | |
| E384 | False flame | Check the correct operation of the gas valve. | |
| E385 | Under voltage | Check the power supply (V~). | |
| E430 | Water pressure temporary test | Check the correct circulation of the water and the pump. | |
| E430 + Flame 'crossed' | Water pressure test failed | Check the correct circulation of the water and the pump |