Emergency
Complaints of noise (5) on Chaffoteaux Flexiflame 140

Your boiler is struggling to control its fuel supply, which can cause loud banging noises and prevents the unit from shutting down safely.

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

Gas valve sticking 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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