Emergency
C551A on Myson Wallflame WF IV

Your boiler has detected an issue with the sensor that confirms the burner flame is lit, causing it to shut down for safety reasons.

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

mechanical fame detector

From this model's manual
Verified against the Myson Wallflame Wf Iv installation & service manual, page 20.
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

C551BView →C551CView →

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