BoilerFaultCodesYour boiler has paused heating the water because it has already reached the target temperature you selected on the control dial.
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: The boiler has a call for hot water but the appliance has reached the desired temperature set on the boiler
What causes this fault?
This occurs when the burner shuts off because the water inside the boiler has successfully reached the temperature you set on the dial. It is a normal safety and efficiency feature that prevents the unit from overheating while it waits for the water to cool down slightly before firing up again. This most commonly happens when the tap is turned down low or the radiators are already very hot.
This code is more frequent in summer when the incoming cold water supply is warmer, meaning the boiler reaches its target temperature much faster than in winter.
DIY fix possible
Check if your hot water taps are turned offReduce the hot water temperature dial slightly if the water is too hotWait for the 'D' to disappear once the water temperature drops and the boiler resumes normal operation
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