High
1A, 1B on Viessmann A8

Your boiler's burner has shut down because it isn't receiving enough air or fuel to ignite safely, meaning you will have no heating or hot water until it is fixed.

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

Burner blocked

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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