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Halo screen shows Replace Halo on Ideal Halo Air RF WI FI 2 Zone

Your thermostat needs to be officially paired or registered with the boiler's receiver to start controlling your heating.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

If you have no other Halo thermostats connected to the Smart Interface or are not replacing an existing Halo then press accept.

What causes this fault?

This message occurs when the thermostat loses its digital connection to the receiver or hasn't had its initial setup completed. It physically means the handheld unit and the boiler interface are no longer talking to each other, preventing the thermostat from sending temperature commands to the boiler. This is usually caused by a recent power cut, depleted batteries, or the device being moved too far from the boiler's wireless range.

DIY fix possible

Press the 'Accept' button on the Halo screen to confirm this is your primary thermostatFollow the on-screen prompts to complete the pairing process with the Smart InterfaceIf the message persists, remove the batteries for 30 seconds and reinsert them to restart the setup

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