F0 and fault indicator LED (and possibly RESET button) are flashing. Internal failure
| Step | Check | Action | |
|---|---|---|---|
| 1. | Button reset flashing? | yes: | ▶ Press the reset button for 3 seconds and release it. After releasing the appliance re-starts. ▶ Initiate demand for heat by pressing the boost button for 10 seconds and then press again after 30 seconds to cancel. ▶ Initiate two more demands for heat as above. F0? go to 2 |
| no: | go to 2 | ||
| 2. | The PCB is damaged. | ▶ Make a note of the altered service settings. ▶ Switch OFF the appliance. ▶ Disconnect the boiler power connection. ▶ Change PCB control board. ▶ Reconnect the appliance power connection. ▶ Switch ON the appliance. ▶ Restore service settings previously noted down. |
