BoilerFaultCodesYour boiler is struggling to control the speed of its internal pump, meaning water may not be circulating through your radiators efficiently.
This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.
Technical description: Pump speed target value
What causes this fault?
This fault occurs when the boiler’s central brain cannot reach or maintain the specific speed it has set for the internal pump. The most common reason is a mechanical failure within the pump motor itself or a communication error where the electrical signals between the control board and the pump are interrupted.
This issue often surfaces at the start of autumn when the heating is turned back on after months of inactivity, as pump components can seize up during the summer.
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 D.14 — no call-out fees, no surprises.
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