Emergency
F.763 on Viessmann Vitodens 222-F B2TF

Your boiler has detected that the incoming gas supply pressure is higher than it is designed to handle, forcing it to shut down for safety.

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

System in a fault state. Gas pressure too high.

From this model's manual
Verified against the Viessmann Vitodens 222 F B2tf installation & service manual, page 108.
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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Related fault codes

F.761View →F.762View →

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