BoilerFaultCodesYour boiler has stopped heating because water is not moving through the system properly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: No water flow
What causes this fault?
This fault occurs when the boiler's internal sensors detect that water isn't moving through the unit quickly enough to safely carry heat away. The most common reason is a failed circulation pump or a blockage in the central heating pipes, such as built-up sludge or a closed valve. Because the water stays still, it would overheat the heat exchanger, so the boiler shuts down as a safety precaution.
This issue is more frequent in autumn when the heating is turned back on after a long summer break, as internal pump parts can seize up from lack of use.
DIY fix possible
Check that your home's water pressure gauge is between 1 and 1.5 barOpen all radiator valves and ensure no radiators are blocked by airRestart the boiler by pressing the 'Reset' button
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A boiler cover plan would cover faults like FD — 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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