BoilerFaultCodesYour boiler has no power going to it at all, meaning the screen is blank and it won't respond to any commands.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: All power off.
What causes this fault?
This fault occurs when the boiler's electrical heartbeat is interrupted, preventing the control system from waking up. The most common reason is a blown internal fuse or a failed main circuit board that can no longer distribute power. Occasionally, this is triggered by an external issue like a tripped circuit breaker or a faulty transformer failing to convert the voltage correctly.
This issue is more common during the autumn and winter months when electrical surges from storms or increased demand on the grid can damage sensitive internal components like the circuit board.
DIY fix possible
Check if your main electrical consumer unit has trippedEnsure the fused spur switch next to the boiler is turned onCheck the 3-amp fuse inside the boiler's wall switch
Find a Gas Safe engineer
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