BoilerFaultCodesYour boiler has lost power because it is switched off at the front, there is no electricity reaching the unit, or an internal fuse has blown.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Facia on/off switch off, no 230V AC supply, or blown fuse F1.
What causes this fault?
This fault occurs when the boiler's internal computer loses its electrical connection, essentially leaving the unit without the power it needs to operate. The most common reasons are that the main power switch on the front panel has been turned off, a fuse on the circuit board has popped, or there is an external issue with the electrical supply to the house. It can also happen if the control board itself has suffered a component failure and can no longer process electricity.
DIY fix possible
Check that the on/off dial on the front of the boiler is set to a 'on' positionEnsure the main electrical isolation switch (usually a white switch near the boiler) is turned onCheck your home's consumer unit (fuse box) to see if a circuit breaker has tripped
Find a Gas Safe engineer
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A boiler cover plan would cover faults like FAIL POINT A — no call-out fees, no surprises.
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Worcester Bosch 25si and 28si is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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