High Lockout
E83462 on Potterton Powermax HE

Your boiler has detected a communication failure or a malfunction with the gas valve, meaning it cannot safely light the flame to provide heating or hot water.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Gas Valve Assembly c/w 3 off ‘O’Rings

What causes this fault?

This fault occurs when the boiler's main control board loses its electronic link with the gas valve or detects that the valve is failing to open correctly. The most common reason is an internal electrical failure within the valve assembly itself or a loose connection in the wiring harness that prevents the command to release gas from being received.

Engineer required

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

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