Emergency
20 on Alpha Intec 40GS2

Your boiler is confused because it senses a flame inside when it shouldn't be there, or it detects a flame when it has not yet commanded the gas to turn on.

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

Flame sensing fault - False flame detection / Flame detected but gas valve is not open

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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Related fault codes

E20View →

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