BoilerFaultCodesYour boiler has detected that water is not circulating correctly through the system, which is preventing it from heating up safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Go to section 'C'
What causes this fault?
This fault occurs when the boiler's internal sensors detect that water isn't moving through the unit fast enough to safely carry heat away. The most common reasons are a worn rubber diaphragm that fails to trigger the switch, a seized circulation pump, or a blockage caused by a build-up of sludge in the system.
This issue often appears when the heating is first turned on after summer, as the internal pump can seize or stick during long periods of inactivity.
DIY fix possible
Check that your system pressure is between 1 and 1.5 bar on the pressure gaugeIf pressure is low, use the filling loop to top it upEnsure all radiator valves and isolation valves are fully openTry resetting the boiler by turning the control knob to the 'R' position for 5 seconds
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like neon flashing (Primary flow switch) — no call-out fees, no surprises.
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Potterton Performa 30 HE 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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