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

Your 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.

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 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 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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