BoilerFaultCodesYour boiler is simply warming itself up to prevent internal components from freezing during very cold weather.
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: Appliance frost protection is activated (pre heating the heat exchanger)
What causes this fault?
The boiler's internal sensors have detected that the water temperature inside the unit has dropped to a very low level, posing a risk of freezing. To protect itself, the burner automatically fires at a low level to gently warm the heat exchanger until it reaches a safe operating temperature. This isn't a fault, but a proactive safety feature designed to prevent the pipes inside the casing from bursting.
This status code is almost exclusively seen during the winter months or during sudden overnight cold snaps when outside temperatures drop below freezing.
DIY fix possible
No action is required as this is a normal safety function.Ensure your condensate pipe has not frozen if it is located outside.Wait for the boiler to finish its pre-heating cycle and return to normal operation.
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