BoilerFaultCodesYour boiler is trying to circulate water but cannot find enough pressure or flow to do so safely, often because the system is low on water.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: pump has run dry
What causes this fault?
This fault occurs when the boiler's internal sensors detect that the pump is spinning without moving enough water through the heat exchanger. The most common reason is a drop in system pressure due to a leak or recent radiator bleeding, but it can also happen if there is a physical blockage or an air lock preventing flow. Use the pressure gauge to check if the needle has fallen below the normal operating zone.
This issue is frequently seen in autumn when homeowners turn their heating back on for the first time, as small leaks over the summer can lead to a significant drop in pressure.
DIY fix possible
Check the pressure gauge on the front of the boiler; if it is below 1 bar, it needs topping up.Locate the filling loop (usually a silver braided hose underneath the boiler) and slowly open the valves until the gauge reaches 1.5 bar.Ensure all radiator valves are open and not blocked by air; bleed radiators if necessary and re-check pressure.Press the Reset button on the boiler control panel.
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A boiler cover plan would cover faults like A1 — no call-out fees, no surprises.
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Worcester Bosch R30 35 And 40 HE Plus 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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