BoilerFaultCodesYour boiler is currently working to provide hot water to your taps or shower, which is a normal status message rather than an actual fault code.
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: Hot water demand
What causes this fault?
This status appears when the boiler detects a flow of water through the internal heat exchanger, signaling a request for hot water. It confirms that the sensors have successfully identified that a tap or shower is turned on and the burner is firing to heat that water. Since this is an operational message rather than a breakdown, it simply means the system is doing exactly what it was designed to do.
DIY fix possible
Check if any hot water taps are currently turned onEnsure there are no leaking or dripping hot water taps in the propertyIf the code remains when all taps are off, check your pre-heat settings or potential internal leaks
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A boiler cover plan would cover faults like S.10 — no call-out fees, no surprises.
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Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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