BoilerFaultCodesYour boiler is struggling to push excess heat away from the unit after it has finished firing, which is usually caused by a water circulation problem.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Pump overrun
What causes this fault?
This fault occurs when the boiler cannot shed heat quickly enough after it has finished heating your home or water. The most common reason is that the internal pump has failed or is struggling to move water through the system, leaving stagnant, scalding water trapped inside the heat exchanger. It can also be caused by a faulty sensor or control board failing to tell the pump to keep running for those vital few minutes after the burner turns off.
This fault is more frequent in autumn when heating systems are turned back on after a long summer break, as pumps often seize up during periods of inactivity.
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 8 — no call-out fees, no surprises.
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Potterton Envoy Plus 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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