BoilerFaultCodesYour boiler has temporarily stopped heating water to prevent it from overheating and will automatically restart once it has cooled down.
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: Boiler in hot water anti-cycle mode
What causes this fault?
This happens when the boiler identifies that the water temperature has risen too quickly or is too high for the current demand, triggering a brief pause to protect internal components. It is often caused by a sudden reduction in water flow, such as turning off a hot tap quickly, or by settings being adjusted to a temperature higher than the system can currently dissipate. The boiler is essentially taking a 'breather' to shed excess heat before firing up again.
This code may appear more frequently in summer when the incoming cold water mains temperature is higher, meaning the boiler reaches its target temperature much faster than in winter.
DIY fix possible
Wait up to 15 minutes for the anti-cycle timer to finishEnsure your hot water taps are fully closedCheck that the hot water temperature setting on the boiler display is not set unnecessarily high
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