Emergency
34 on Alpha 240XE

Your boiler has detected that the air supply or exhaust system is not working correctly, meaning it has safely shut down to prevent unsafe gases from building up.

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

Room sealed chamber

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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