BoilerFaultCodesYour boiler is struggling to circulate water, most likely because the system pressure has dropped too low or the internal pump is stuck.
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 water isn't moving through the heat exchanger fast enough to safely carry heat away. The most common reason is that the system pressure has dropped too low for the pump to work, or the pump itself has seized after a period of inactivity.
This issue is frequently seen in autumn when the heating is turned on for the first time after summer, as the internal pump can often become stuck during the warmer months.
DIY fix possible
Locate the pressure gauge on the front of the boilerIf the needle is below 1 bar, use the filling loop valves underneath the boiler to top it up to 1.5 barTurn the selector switch to the reset position for five seconds and then back to the heating/hot water mode
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A boiler cover plan would cover faults like 26 — 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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