BoilerFaultCodesYour boiler has identified an internal problem and is displaying a specific code number to help pinpoint the exact technical issue.
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?
This fault occurs when the boiler's internal computer detects a specific malfunction within the operational sequence, such as a failure to ignite or a component communication error. The most common reasons involve a lack of fuel supply, a failure to vent exhaust gases properly, or an electrical fault within the main control system. Because the 'F' code is a prefix, it indicates that a primary safety or operational sensor has triggered a complete system shutdown.
While this can happen year-round, it is more frequent during cold snaps when internal components are under higher strain or external pipes are prone to freezing.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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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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