Emergency
20 on Alpha E-Tec 24

Your boiler has detected heat or fire inside the unit even when it hasn't turned the gas on, so it has shut down to keep your home safe.

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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