F And Burner Light Low
Your boiler has detected very cold temperatures and has automatically turned itself on to prevent the internal pipes from freezing.
Technical description: The boiler is operating in frost mode
Typical repair cost: £0 (including labour)
DIY fix possible
No action is required as this is a normal safety function.The boiler will stop this mode automatically once the water temperature inside the unit rises sufficiently.Ensure your external condensate pipe is not frozen if temperatures are extremely low.
Protect yourself from future repair bills
A boiler cover plan would cover faults like F And Burner Light — no call-out fees, no surprises.
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