BoilerFaultCodesYour boiler has detected an internal electrical or mechanical fault that is preventing it from circulating water around your home.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: The boiler has defaulted to a fault mode (Section B - Pump/PCB fault)
What causes this fault?
This fault occurs when the boiler's internal components fail to move water through the heat exchanger, causing the system to stall. The most common reason is a seized or failed circulation pump, though it can also be triggered by a communication error on the main control board that prevents power from reaching the pump.
This issue often surfaces at the start of autumn when a pump that has been idle all summer becomes seized with limescale or sludge upon restart.
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 neon flashing — no call-out fees, no surprises.
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Potterton Performa System E 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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