BoilerFaultCodesYour boiler has no power and is completely unresponsive, 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 domestic hot water or central heating. Check: 230V supply, fuse, loose connections on control board (PCB), or faulty control/interface board.
What causes this fault?
This fault occurs when the boiler's electrical circuit is broken, preventing power from reaching the internal components. The most common reason is a blown fuse or a total failure of the main control board, which acts as the brain of the appliance. Without this steady flow of electricity, the boiler cannot ignite or communicate with your thermostat.
This issue often follows a local power surge or a nearby lightning strike during summer or winter storms, which can overload and damage the sensitive electronics on the control board.
DIY fix possible
Check if other appliances in your home have power to rule out a general power cutEnsure the boiler's 230V isolation switch (fused spur) is turned onCheck your home's main consumer unit (fuse box) to see if a circuit breaker has tripped
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A boiler cover plan would cover faults like No flashing warning light on control panel — no call-out fees, no surprises.
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