BoilerFaultCodesYour boiler is unable to circulate water around the system, meaning your heating and hot water will not work.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Contact Installer
What causes this fault?
This fault occurs when the boiler's internal pump is unable to move water through the heat exchanger, often due to a mechanical failure or a build-up of debris known as magnetite. It can also be caused by a communication failure where the main control board is unable to send power or signals to the pump motor.
This issue is more frequent in autumn when heating systems are turned back on after a summer of inactivity, which can cause internal 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 Pump Fault — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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