BoilerFaultCodesYour boiler is notifying you that it has automatically switched between summer and winter mode based on the external temperature.
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: Automatic summer/winter changeover
What causes this fault?
This notification occurs when the outdoor temperature sensor detects a change in the weather that crosses a pre-set threshold. The boiler is simply informing you that it has automatically turned the central heating off for the summer or back on for the winter to save energy. It is a sign that the system's intelligent weather compensation is working correctly to manage your home's efficiency.
This code is most common during the transition periods of spring and autumn when outdoor temperatures fluctuate across the changeover trigger point.
DIY fix possible
Check your external temperature sensor for any obstructions or damageReview your heating settings if the boiler switched modes at an unexpected timeNo action is required if your heating and hot water are working as desired
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