BoilerFaultCodesYour boiler's internal computer has crashed due to an ignition failure or electrical interference, preventing it from starting the burner.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Burner in fault position. Control unit fault. Check the ignition electrodes and leads. Check whether there is a strong interference field (EMC) near the appliance.
What causes this fault?
This fault occurs when the boiler's internal computer experiences a critical communication error or fails to verify the ignition process. The most common reasons are worn-out spark electrodes that can no longer light the gas, or electrical 'noise' from nearby appliances interfering with the boiler's sensitive electronics.
DIY fix possible
Press the reset button or turn the boiler off and back on at the fused spur switchEnsure large electronic devices or powerful wireless routers are not sitting directly next to the boilerCheck if other gas appliances in your home are working to ensure gas is reaching the property
Find a Gas Safe engineer
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A boiler cover plan would cover faults like Fd — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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