High
20 on Alpha Intec 24GS

Your boiler is confused because it detects a flame inside when it hasn't actually turned the gas on yet, so it has safely locked itself to prevent an unsafe start-up.

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

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

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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Related fault codes

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