BoilerFaultCodesTechnical description
With DHW priority applicable to mixer: The mixer is closed whilst DHW is loaded; the heating circuit pump operates
What causes this fault?
This status occurs because your boiler is designed to prioritise heating your hot water tank over your radiators. It physically closes a mixing valve to direct all available heat to your water cylinder, ensuring you have a full tank of hot water as quickly as possible. Once the water tank reaches its target temperature, the boiler will automatically switch back to heating your home.
DIY fix possible
Wait for the hot water tank to reach its target temperatureCheck if the hot water timer or 'boost' function is activeOnce the water is hot, the heating should automatically restart
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