BoilerFaultCodesYour boiler has switched itself off because the water pressure is too low or the pump that moves water around your radiators isn't working correctly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Fault on Pump or Low System Pressure
What causes this fault?
This fault occurs when the boiler detects that there isn't enough water pressure to safely operate or that water isn't being pushed through the internal heat exchanger. The most common reason is a simple drop in system pressure, but it can also be triggered if the pump has seized or failed due to age. If the water cannot move, the boiler shuts down to prevent the internal components from overheating.
This issue is frequently seen in autumn when the heating is turned on for the first time after summer, as pump components can seize during long periods of inactivity.
DIY fix possible
Locate the pressure gauge on the front of the boiler to see if it is below 1 bar.Find the filling loop (usually a silver braided hose with two small valves) underneath the boiler.Slowly open both valves until you hear water entering and the gauge reaches between 1 and 1.5 bar, then close them tightly.
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A boiler cover plan would cover faults like 26 — 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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