BoilerFaultCodesYour boiler is notifying you that it has reached the maximum temperature allowed for your hot water cylinder.
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: Maximum set value for target cylinder
What causes this fault?
This occurs when the temperature sensor in your hot water cylinder detects that the water has reached the maximum safety limit you have set. It acts as a safety gate to prevent the water from becoming dangerously hot or scalding. The issue is often caused by the settings being adjusted too high or a sensor that is starting to provide inaccurate readings to the boiler.
DIY fix possible
Check the hot water temperature settings on your boiler control panelReduce the target cylinder temperature if it is set too highMonitor the boiler to see if the code clears once the water temperature stabilizes
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