BoilerFaultCodesYour boiler has stopped working because there is not enough water flowing through the system to keep it running safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Burner in fault position. Water flow too low. Check the heating system pressure, the pump and the flue gas/water heat exchanger.
What causes this fault?
This fault occurs when the boiler's internal sensors detect that water isn't moving through the unit fast enough to safely carry heat away from the burner. The most common reasons are a failing internal pump that can no longer push the water or a significant blockage within the main heat exchanger. It can also be triggered by a build-up of sludge in the system pipes that restricts overall flow.
This issue often surfaces in autumn when the heating is turned back on after a long summer break, as pump components can seize during periods of inactivity.
DIY fix possible
Check the pressure gauge on the front of the boiler; if it is below 1.0 bar, top it up using the filling loop.Ensure all radiator valves are fully open to allow water to circulate.Gently bleed air from your radiators using a radiator key.
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A boiler cover plan would cover faults like E6 — no call-out fees, no surprises.
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Could it be time for a new boiler?
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