BoilerFaultCodesWhat the manual says
Manufacturer manualFlame detection fault (flame presence for more than 5 seconds after burner stopped). Gas valve defective
Shared across the range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
What causes this fault?
This fault occurs when the boiler's safety sensors continue to detect heat or electrical signals from a flame even after the gas should have been cut off. The most common reasons are a sticking gas valve that isn't closing fully, a damaged sensor probe that is sending incorrect signals, or a fault within the main control board.
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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