BoilerFaultCodesYour boiler's internal pump has failed or is struggling to circulate water, meaning your heating and hot water will likely stop working.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Pump c/w auto air vent & 2 off washers
What causes this fault?
This fault occurs when the boiler's internal pump can no longer move water through the system effectively, often due to a mechanical failure or debris causing the pump to seize. It can also be triggered by a build-up of air within the unit that prevents the pump from gaining the necessary prime to circulate heat. If the pump cannot move the water, the boiler shuts down to prevent the internal heat exchanger from dangerously overheating.
This issue often surfaces in autumn when the heating is turned back on after being idle all summer, as stagnant water can cause pump components to seize.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like E85761 — no call-out fees, no surprises.
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