BoilerFaultCodesYour boiler has stopped working because the water isn't circulating properly, likely due to a pump issue or trapped air in the system.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Pump-related faults – the pump could have failed, it may have over run or there could be an issue with the airlock
What causes this fault?
This fault occurs when the boiler detects that water is not moving through the system quickly enough to safely carry heat away from the burner. The most common reasons are a circulation pump that has seized or lost power, or a large pocket of air trapped within the unit that is blocking the flow of water. In some cases, it can also be triggered by a build-up of debris or sludge that has restricted the internal pipework.
This issue often appears in autumn when the heating is turned on for the first time after summer, as pumps can seize if they have been sitting idle for several months.
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.24 — no call-out fees, no surprises.
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