BoilerFaultCodesYour boiler is simply letting you know it is currently busy heatng up your hot water tank or keeping its internal water reserve warm.
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 holding request / Cylinder charging request
What causes this fault?
This occurs when the boiler prioritizes your hot water over your central heating to ensure you have a full tank or a primed internal heat exchanger. It is triggered when the physical sensors detect the water temperature has dropped below a set point, prompting the boiler to fire up specifically for hot water. This isn't a failure, but rather a notification that the system is temporarily busy focusing its energy on your taps and showers.
This status is more noticeable in winter when the incoming mains water is colder, requiring the boiler to work longer to reach the necessary temperature for your cylinder.
DIY fix possible
Check your hot water timer or thermostat settings to see if it is currently scheduled to be onWait a few minutes to see if the status changes back to heating or standby naturallyTurn off 'Comfort Mode' using the radiator dial if you want to stop the boiler from pre-heating its internal tank
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