High Lockout
HP Comms No illumination on Ideal Halo Air RF WI FI 2 Zone

Your smart thermostat is unable to talk to your boiler because the wired connection between them has been lost or disconnected.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 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 is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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