BoilerFaultCodesYour boiler is displaying a status message indicating the target temperature for the 'warm start' feature, which keeps water inside the unit pre-heated for faster hot water delivery.
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: Warm start temperature target value
What causes this fault?
This is a normal status code rather than a mechanical failure. It appears when the boiler's internal software is calculating the specific heat level required to keep a small amount of water pre-warmed inside the unit. This ensures that when you turn on a tap, you receive hot water almost instantly rather than waiting for the burner to heat up from cold.
DIY fix possible
Check if the 'C' symbol is displayed on the screen, which indicates warm start is active.Turn the domestic hot water temperature knob fully clockwise to enable or counter-clockwise to disable the feature if preferred.No action is required if your hot water is working normally, as this is an information code rather than a breakdown.
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