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: DHW being supplied
What causes this fault?
This code appears when the boiler detects a demand for hot water, usually because a tap or shower has been turned on. The internal flow sensor triggers the boiler to fire up and redirect heat to your domestic water supply rather than your radiators. It is a normal part of the boiler's operation and simply confirms that the system is working as intended.
DIY fix possible
Check if any hot water taps are currently turned on.Ensure any mixer showers are fully turned off.If no taps are open but the code remains, check for a dripping hot water tap.
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