BoilerFaultCodesYour boiler is failing to keep its small starter flame lit, which prevents the main heating system from firing up.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: PILOT WILL NOT STAY LIT WHEN THE GAS CONTROL VALVE KNOB IS RELEASED
What causes this fault?
This fault occurs when the boiler's safety mechanism fails to detect a constant flame, causing it to shut off the gas supply for safety. The most common reason is a worn-out sensor called a thermocouple that can no longer signal that the pilot light is safely lit, or a slight blockage in the pilot burner preventing a strong flame. In some cases, it may also be triggered by an internal safety switch that has tripped to prevent the unit from overheating.
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 50 — no call-out fees, no surprises.
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