BoilerFaultCodesYour boiler has stopped working because the water pressure inside the system has dropped too low.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: The water pressure is less than 0.5 bar. Check the water pressure and top up the system
What causes this fault?
This fault occurs when the internal sensors detect that there isn't enough water volume to safely transfer heat around your home. The most common reason is a slow leak in the radiator network or pipework, but it can also happen if you recently bled your radiators without topping up the pressure afterwards.
This issue often surfaces when you turn the heating back on for autumn, as the system settles after being dormant or develops leaks from expanding and contracting metal.
DIY fix possible
Locate the filling loop (usually a silver flexible hose) underneath the boiler.Slowly open the one or two taps/levers on the hose until you hear water entering.Watch the pressure gauge and close the taps once it reaches between 1.0 and 1.5 bar.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like 50° neon flashing — no call-out fees, no surprises.
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Potterton Performa 24 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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