Emergency
UNSTABLE FLAMES on Chaffoteaux Corvec 28 OF BF

Your boiler is struggling to keep the fire lit safely, which could prevent your heating or hot water from working consistently.

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

i) Water in gas line ii) Inlet pressure too high for governor iii) Faulty flue

From this model's manual
Verified against the Chaffoteaux Corvec 28 Of Bf 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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