BoilerFaultCodesYour boiler has detected very cold temperatures and has automatically turned on to prevent the internal water from freezing and damaging the pipes.
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: Frost protection: If the heat exchanger temperature falls too low, the burner switches on and the pump runs until the heat exchanger temperature is sufficient (pre heating the heat exchanger).
What causes this fault?
This code appears when the internal temperature sensors detect that the water inside your boiler has dropped to a level where it might freeze. To prevent the heat exchanger from cracking due to ice expansion, the boiler automatically fires the burner and starts the pump to circulate warm water. The unit hasn't stopped working; it is simply performing a self-preservation routine to keep the system safe.
This code is almost exclusively seen during the winter months or during periods of extreme cold when temperatures drop near freezing.
DIY fix possible
No action is required as this is a normal safety function.Ensure your boiler remains connected to the electricity supply.Check that your external condensate pipe is not frozen if temperatures are below zero.
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