Immergas Phase / Neutral / Earth Wiring Fault

Furnace shows 20, no operation, may be after incorrect wiring or a power event.

This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.

If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.

Possible Causes

Incorrect mains polarity, Missing earth connection, Shared neutral with other circuits causing interference

Safety: Electrical work must comply with local regulations. If you are not competent, call an electrician.

Steps:

1. Check plug/socket: If the boiler is connected via a plug, ensure it is fully inserted and not damaged.
2. Verify dedicated circuit: The boiler should be on a dedicated fused spur or breaker. Avoid sharing the circuit with high-load appliances.
3. Electrician checks: An electrician should verify the correct phase/neutral orientation, the presence of a reliable earth, and the correct voltage at the boiler terminals.

Hard 4/5