BoilerFaultCodesYour wireless smart thermostat is too far away from the boiler's receiver, causing a weak connection that might cause your heating to stop responding.
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: Consider moving the Halo closer to the Air Interface. If the situation persists then consider using Zigbee Booster.
What causes this fault?
This fault occurs when the wireless signal between your thermostat and the boiler becomes too weak to communicate reliably. It is usually caused by building materials like thick stone walls or foil-backed insulation blocking the signal, or the thermostat simply being placed too far from the boiler's receiver.
DIY fix possible
Move the Halo thermostat closer to the boiler's Air Interface unit.Ensure there are no large metal objects or thick walls blocking the line of sight between the devices.If the signal remains red, purchase and install a Zigbee signal booster.
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A boiler cover plan would cover faults like Zigbee RSSI is lower than -65 and text red — no call-out fees, no surprises.
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