BoilerFaultCodesYour boiler's small pilot light is on, but the main heating flame is failing to ignite, meaning your central heating will not work.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Main burner fails to light, pilot burning.
What causes this fault?
This fault occurs when the gas valve fails to release fuel to the main burner even though the pilot light is ready and waiting. The most common reason is an electrical failure in the solenoid coil or a mechanical blockage within the burner injectors that prevents the gas from flowing. Because the main flame cannot catch, the boiler stays in a standby state and cannot produce heat for your radiators.
This issue often comes to light during the first cold spell of autumn when the gas valve's internal components stick after being inactive throughout the summer.
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 C — no call-out fees, no surprises.
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Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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