BoilerFaultCodesYour smart thermostat is currently in pairing mode and is searching for a connection to your heating system or internet gateway.
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: Pairing
What causes this fault?
A flashing red Zigbee light indicates that the thermostat or wiring centre has been manually put into pairing mode or has lost its existing link and is actively searching for a connection. This is typically triggered during the initial setup, after a power cut, or if the wireless signal between the devices has been interrupted for an extended period. It is not an internal mechanical failure but rather a communication state where the device is waiting to sync with your heating system.
DIY fix possible
Ensure your Smart Interface (connected to the boiler) is also in pairing mode.Follow the on-screen instructions on your Halo thermostat to complete the setup.Wait up to 2 minutes for the light to turn solid green, indicating a successful connection.
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A boiler cover plan would cover faults like Zigbee Red (flashing) — no call-out fees, no surprises.
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