BoilerFaultCodesYour boiler has detected that the internal pump, which moves water around your pipes and radiators, is not working correctly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Pump Fault: Check pump wiring, if OK replace pump
What causes this fault?
This fault occurs when the boiler's control board detects that the internal pump is not spinning or drawing the correct amount of electricity. The most common reason is that the pump has seized due to a buildup of debris or sludge in the system water, or the motor has simply failed after years of heavy use.
This fault is more common in autumn when the heating is turned on for the first time after summer, as the pump can seize if it has been sitting idle for several months.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like F17 — 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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