BoilerFaultCodesYour boiler has stopped working because water is not moving through the system properly, causing it to overheat and shut down for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Water Circulation LOCKOUT
What causes this fault?
This fault occurs when the water inside the boiler gets too hot because it isn't being moved away into your radiators or hot water tank quickly enough. The most common reason is a failed internal pump or a blockage in the pipework that is preventing the water from flowing. As a safety precaution, the boiler shuts itself down to prevent damage from overheating.
This issue often appears when you first turn the heating back on in autumn, as the internal pump can seize up after sitting idle during the summer months.
DIY fix possible
Check that your central heating valves and radiator valves are openCheck that your boiler pressure is between 1 and 1.5 bar on the gaugeTurn the selector switch to 'Reset' for five seconds and then back to its original position
Find a Gas Safe engineer
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Gas Safe Register →Protect yourself from future repair bills
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Potterton Performa SL HE 9 2 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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