BoilerFaultCodesYour boiler thinks it can see a flame even though it hasn't started the ignition process yet, which prevents it from running for safety reasons.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flame signal without flame present – air/gas ratio control valve may need replacing as might the ionisation cable
What causes this fault?
This fault occurs when the boiler's internal sensor detects an electrical signal signifying a flame at a time when the burner should be off. The most common reason is a faulty detection electrode sending a false signal or a gas valve that is leaking slightly, allowing a small amount of fuel to stay lit. Because the boiler cannot safely confirm the fire is out, it shuts down to prevent any risk of overheating or gas build-up.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like 228 V — no call-out fees, no surprises.
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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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