BoilerFaultCodesYour boiler has detected that there is either not enough water in the system or the pump is struggling to move it around 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 a lack of water circulation, preventing it from safely transferring heat away from the burner. The most common reason is low water pressure in the system, but it can also be caused by a mechanical failure of the pump or a blockage that is stopping the water from flowing.
This issue is frequently seen in autumn when heating systems are turned back on after summer, as pump components can seize up during long periods of inactivity.
DIY fix possible
Locate the pressure gauge on the front of the boilerIf the needle is below 1.0, use the filling loop underneath the boiler to top up the waterSlowly add water until the gauge reads between 1.0 and 1.5 bar, then ensure the valves are tightly closed
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A boiler cover plan would cover faults like 9 — no call-out fees, no surprises.
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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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