BoilerFaultCodesYour heating control box on the boiler has no power lights and is unable to talk to your thermostat.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Check Smart Interface is securely plugged into the interface bracket. Check power to bracket.
What causes this fault?
This fault occurs when the communication hub attached to your boiler loses its electrical supply or fails internally. It is usually caused by the unit being vibrated loose from its bracket or a failure in the wiring harness that connects the controls to the boiler's main circuit board.
DIY fix possible
Ensure the boiler's main power switch is turned onCheck that the Smart Interface module is pushed firmly into its bracket on the boilerCheck your home's fuse box for any tripped switches
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A boiler cover plan would cover faults like No power LED on Smart Interface — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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