BoilerFaultCodesYour boiler is struggling to move water around the system properly, which is causing it to shut down to prevent overheating.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Circulation
What causes this fault?
This fault occurs when the water inside the boiler is heating up too quickly because it isn't being pumped away fast enough. The most common reasons are a failed internal pump, a build-up of sludge blocking the pipes, or air trapped within the system that prevents smooth circulation.
This issue often surfaces in autumn when the heating is turned back on after being idle all summer, which can cause the pump to seize.
DIY fix possible
Check that all radiator valves are fully openEnsure the boiler pressure is between 1.0 and 1.5 barTry bleeding your radiators to remove any trapped air
Find a Gas Safe engineer
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A boiler cover plan would cover faults like E193 — no call-out fees, no surprises.
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Potterton Promax 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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