BoilerFaultCodesYour boiler is unable to move hot water around the system, meaning your heating and hot water will not work.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Fault detected with the pump. Check pump connections, water flow, or replace pump.
What causes this fault?
This fault occurs when the boiler's internal computer detects that water is not circulating through the heat exchanger correctly. The most common reasons are a mechanical failure of the pump motor, a buildup of sludge blocking the internal pipework, or a loose electrical connection between the pump and the main control board.
This issue is frequently seen in autumn when heating systems are switched back on after being idle all summer, which can cause the pump's internal bearings to seize up.
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 PUMP FAULT — no call-out fees, no surprises.
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Ideal Concord CXA 40-120 is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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