BoilerFaultCodesYour boiler is simply letting you know that someone has turned on a hot tap and it is currently busy heating water for your shower or sink.
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: domestic hot water demand
What causes this fault?
This code appears when the boiler's internal flow sensor detects that water is moving through the hot water pipes. It triggers the burner to ignite so that it can provide an immediate supply of heat to your taps or shower. This is a normal operational message rather than a mechanical failure.
DIY fix possible
Check if any hot water taps have been left running slightlyEnsure your shower is fully turned offNo action is required as this is a normal status message, not a fault
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A boiler cover plan would cover faults like S.10 — no call-out fees, no surprises.
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