BoilerFaultCodesYour boiler's small pilot light has started, but the main burner is failing to ignite to provide heating and hot water.
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 its small pilot flame, but the main burner fails to catch light to start heating your home. This is usually caused by a blockage in the pilot injector that prevents the flame from reaching the sensor, or a mechanical failure within the gas valve that stops the main flow of fuel.
This issue often surfaces during the first cold spell of autumn when the boiler is asked to work harder after sitting idle over the summer months.
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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