BoilerFaultCodesYour boiler has detected a specific internal fault and requires you to check the number following the 'F' on the display to identify the exact problem.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Boiler has a fault for a specific error. Display will show a number after the F to indicate which error is detected.
What causes this fault?
The 'F' display is an indicator that your boiler’s internal computer has detected a malfunction in one of its vital components, such as the fan, gas valve, or ignition system. This happens when the sensors provide readings that fall outside of safe operating limits, causing the boiler to stop working to prevent damage. The specific number following the letter tells the engineer exactly which part of the combustion or circulation process has failed.
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 F — 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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