BoilerFaultCodesYour boiler has reached the maximum allowed temperature for heating your hot water cylinder and is pausing operation as a standard safety limit.
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 your boiler reaches its temperature limit while heating your hot water cylinder, causing it to pause temporarily to prevent overheating. It often happens because the boiler is producing heat faster than the cylinder can absorb it, which is typical once the water in the tank is nearly at its target temperature. The boiler is simply regulating itself rather than failing.
DIY fix possible
Check the hot water temperature setting on the boiler control panelReduce the target cylinder temperature if it is set unnecessarily highWait for the system to cool down naturally before the boiler resumes
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