BoilerFaultCodesYour boiler has detected very cold water in the storage tank and has paused operation as a safety measure to prevent the internal pipes from freezing.
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: If the domestic cold water is below 10OC the tank frost protection may operate and a F1 will be displayed
What causes this fault?
This fault occurs when the temperature sensor inside your hot water storage tank detects that the water has dropped to a near-freezing level. To protect the internal components from being damaged by expanding ice, the boiler temporarily pauses operation until the water temperature rises to a safe level. This is typically caused by extremely cold incoming mains water or a storage tank located in an unheated area like a garage or loft.
This fault is almost exclusively seen during the winter months when external temperatures drop significantly and reduce the temperature of the incoming mains water.
DIY fix possible
Wait for the house temperature to rise naturally, which will warm the water in the tank.Ensure any loft hatches are closed and that the boiler area is not exposed to freezing draughts.The fault should automatically clear once the water temperature inside the unit rises above 10°C.
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