BoilerFaultCodesYour boiler's internal pump is either jammed or struggling to move water because there is too much trapped air in the system.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Pump stuck or running with air in the system
What causes this fault?
This fault occurs when the boiler's internal pump is unable to circulate water because it is physically jammed or there is a large pocket of air preventing it from gaining traction. Over time, debris in the system water can seize the pump's moving parts, or air can enter the system after a period of inactivity or a recent repair.
This fault is more common in autumn when homeowners turn their heating back on for the first time, as pumps often seize after being idle throughout the summer.
DIY fix possible
Check your boiler pressure gauge and top it up to 1.5 bar if it is too lowBleed all of your radiators to remove trapped airGently restart the boiler using the reset button
Find a Gas Safe engineer
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Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like A1281 — 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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