BoilerFaultCodesYour boiler has correctly detected that you have turned on a hot water tap and is working as intended.
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: Illuminates whenever there is a demand for hot water i.e. a hot water tap is opened.
What causes this fault?
This indicator is triggered when the boiler's internal flow sensor detects water moving through the pipes after you open a hot water tap. It signifies that the internal components have successfully switched from standby or heating mode to prioritise your hot water needs. Because this is a normal operating signal rather than a malfunction, no intervention is required and your boiler is functioning correctly.
DIY fix possible
No action requiredThis is a normal status indicator, not a fault
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A boiler cover plan would cover faults like Hot water demand indicator (yellow) — no call-out fees, no surprises.
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