BoilerFaultCodesYour boiler's pilot light is going out as soon as you let go of the ignition button, preventing the main burner 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: 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 system fails to detect a steady pilot flame, causing it to shut off the gas supply for safety. The most common reason is a worn-out thermocouple that can no longer generate the small electrical current needed to hold the gas valve open, or a build-up of soot blocking the pilot assembly.
This issue often surfaces during the first cold spell of autumn when a boiler that has been switched off all summer is suddenly forced to work harder.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like 50 — no call-out fees, no surprises.
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