Emergency Lockout
Wiring fault on Potterton Envoy 30

Your boiler has detected an electrical wiring error where the power wires appear to be connected incorrectly, which is a significant safety risk.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

Technical description

Live on neutral connection Correct fault

What causes this fault?

This fault occurs when the boiler detects that the electrical supply wires are reversed, meaning the 'live' and 'neutral' power lines are connected to the wrong terminals. The most common reason is recent electrical work elsewhere in the property or a failing main control board that can no longer correctly identify the incoming power signal.

Engineer required

This is a emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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