BoilerFaultCodesYour boiler is struggling to push water through the heating system, which usually means the pressure is too low or something is blocking the flow.
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 sensors detect that water isn't moving through the unit quickly enough to safely carry heat away. The most common reason is that the system pressure has dropped too low, but it can also be caused by a build-up of sludge or a pump that has seized up and stopped spinning.
This fault often appears during the first cold spell of autumn when the heating is turned on after being idle all summer, which can cause the internal pump to stick.
DIY fix possible
Check the pressure gauge on the front of the boiler; it should be between 1 and 1.5 bar.If the pressure is low, use the filling loop underneath the boiler to top it up.Ensure all radiator valves and isolation valves under the boiler are fully open.
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A boiler cover plan would cover faults like F 0d — 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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