BoilerFaultCodesYour boiler has lost its electrical supply and won't turn on, meaning it cannot provide any heating or hot water.
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 to boiler
What causes this fault?
This fault occurs when the electrical circuit feeding the boiler is interrupted, meaning the control system has no power to operate. The most common reasons are a blown fuse in the external wall switch, a tripped circuit breaker in your fuse box, or a failure of the internal components that manage electricity within the boiler itself.
This fault is more common during the winter months when heavy electrical demand or local power surges can cause external fuses or circuit breakers to trip.
DIY fix possible
Check if other appliances in the house have powerInspect your home's main fuse box (consumer unit) for any tripped switchesCheck the fused spur switch near the boiler to ensure it hasn't been turned off or the fuse hasn't blown
Find a Gas Safe engineer
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A boiler cover plan would cover faults like 79 — no call-out fees, no surprises.
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Worcester Bosch Greenstar Utility 18/25 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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