BoilerFaultCodesYour boiler is simply letting you know that it is currently busy heating up water for your taps or shower.
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: Boiler in hot water mode
What causes this fault?
This is a normal operational message rather than a mechanical failure, occurring when the boiler senses a demand for hot water from a tap or shower. The internal sensors have identified that water is flowing through the heat exchanger, prompting the boiler to temporarily stop heating your radiators to focus all its energy on your hot water.
DIY fix possible
No action is required as this is an operational status message rather than a breakdown.Check that your hot water taps are fully turned off.Wait for the boiler to finish its current cycle, after which the code should disappear.
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A boiler cover plan would cover faults like 201 — no call-out fees, no surprises.
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