| F.63 | EEPROM error: fault in the configuration memory of the boiler's electronics. | The EEPROM physically resides on this main PCB; if the memory becomes corrupted or fails, the cause is the board itself. Verify: after a reset, the code persists and, with correct connections and sensors, the fault reproduces; confirm replacement of the board. |
| F.64 | Electronics error / NTC: fault in the electronics or short circuit in the flow/return NTC sensors. | When a short circuit in the NTC is ruled out (by checking sensors and wiring with a multimeter), the fault in the electronics processing those signals points to this main PCB. Verify: NTC and connections are correct but the fault code persists after reset = defective PCB. |
| F.65 | Temperature error in the electronics: the PCB is overheating. | The temperature sensor of the electronics itself detects excess heat on the PCB; if an external heat source or lack of ventilation is ruled out, the origin is a defect in the PCB. Verify: normal environment/ventilation but the code repeats = faulty PCB. |
| F.61 | Fault in the regulation/activation of the gas valve: the electronics cannot control the gas valve. | The PCB is the one that controls the gas valve; with wiring to ground, short circuit, and the valve itself ruled out using a multimeter, the remaining documented cause is the PCB. Verify: wiring and valve coils are correct but the code persists = defective PCB (the PCB is one of the causes, not the only one). |
| F.62 | Gas valve error due to delayed shutdown: delayed disconnection of the gas valve detected. | The PCB manages the closing/timing of the valve and the electrode signal; with the valve and detection electrode ruled out, the control electronics defect points to this PCB. Verify: valve and electrode are correct but the code repeats = PCB (concurrent cause with valve/electrode). |
