BoilerFaultCodesYour boiler appears to have no power at all, meaning the screen and lights are completely dark and it will not respond.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: No power at control board. Possible solution/check: Permanent mains supply to boiler, Boiler mains switch, Fuse F1 2.5A or Fuse F3 0.5A, Transformer (both coils below 100Ω), Otherwise replace control board.
What causes this fault?
This fault occurs when the electrical circuit within the boiler is broken, preventing power from reaching the internal computer. It is usually caused by a blown fuse following an external power surge or a component failure, such as a faulty transformer or a short circuit on the main control board. Without this electrical flow, the boiler cannot light the flame or operate the pump.
This issue is more common during the winter months when heavy storms and power fluctuations are more likely to cause electrical surges that can blow internal fuses.
DIY fix possible
Check that the boiler's main power switch is turned onCheck your home's main fuse box (consumer unit) to see if a circuit has trippedCheck the fused spur switch (usually located near the boiler) and replace the fuse if necessary
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