BoilerFaultCodesYour smart thermostat display is blank because it has lost its wired connection to the heat pump or boiler interface, preventing you from controlling your heating.
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 your smart thermostat's base and the heating appliance is broken or disconnected. The most common reason is a loose wire or a poor connection at the terminals, which prevents the screen from receiving the power and digital information it needs to function.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like No illumination (HP Comms) — 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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