BoilerFaultCodesYour boiler has detected an internal electrical or gas valve issue that is preventing the pilot light from staying lit, meaning it cannot heat your water or radiators.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Faulty pilot multi-functional control solenoid, harness continuity, or PCB
What causes this fault?
This fault occurs when the boiler's internal computer tries to light the flame but cannot verify that the gas valve has opened correctly. The most common reason is an electrical failure within the valve's solenoid or a communication break in the wiring, which prevents gas from reaching the pilot burner to start the ignition process.
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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