BoilerFaultCodesYour boiler detects a flame when it should be off, which is a safety error that prevents the system from starting up.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flame On Before Gas Valve On
What causes this fault?
This fault occurs when the boiler's sensors detect a flame inside the burner assembly even though the gas valve should be closed. The most common reasons are a gas valve that is leaking slightly and failing to shut off fully, or a faulty sensor lead that is sending a false signal back to the main control board.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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