BoilerFaultCodesYour smart thermostat is unable to talk to your boiler because the wired connection between them has been lost or disconnected.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: HP Comms fault (check BSB wiring)
What causes this fault?
This fault occurs when the physical data link between the boiler's internal computer and the smart interface is broken or interrupted. It is usually caused by a loose connection at the wiring harness or a component failure that stops the two parts from sharing information. Without this constant stream of data, the boiler cannot receive commands from your thermostat to turn the heating on.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like HP Comms No illumination — 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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