BoilerFaultCodesYour boiler has managed to start the small pilot flame, but the main burner fails to ignite to provide full heating.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: PILOT LIT BUT NO MAINS GAS
What causes this fault?
This fault occurs when the boiler successfully lights the small internal pilot flame but the main burner fails to catch fire. The most common cause is a faulty gas valve that isn't opening properly to let the full flow of gas through, or a blockage in the main injector that delivers fuel to the burner.
This issue is frequently seen during the first cold snap of autumn, as gas valves can become stuck or seized after being inactive throughout the summer months.
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 52 — no call-out fees, no surprises.
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