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.

What the manual says

Manufacturer manual

Room sealed chamber

From this model's manual
Verified against the Alpha 240xe installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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