BoilerFaultCodesYour boiler has switched to prioritising hot water because it thinks a tap is currently running somewhere in your home.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: DHW operation: The boiler controller goes to DHW mode when the flow sensor detects a need for more than 2 l/min of DHW.
What causes this fault?
This occurs when the internal flow sensor incorrectly detects water moving through the pipes, even if all your taps are closed. The most common reason is a piece of debris or limescale getting stuck inside the flow turbine, causing it to spin or send a false signal to the boiler. This tricks the system into staying in hot water mode constantly, which often prevents your central heating from turning on.
DIY fix possible
Check that all hot water taps and showers are fully turned off.Inspect for any dripping taps or leaking hot water pipes.Restart the boiler to see if the indicator clears when no water is being drawn.
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A boiler cover plan would cover faults like 6 — no call-out fees, no surprises.
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