BoilerFaultCodesYour thermostat has lost its wireless connection to the boiler, meaning your heating controls cannot talk to the system.
This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.
Technical description: No connection
What causes this fault?
This fault occurs when the wireless signal between your thermostat and the smart interface plugged into the boiler is interrupted or lost. The most common reasons include simple dead batteries in the wall unit, physical obstructions like new furniture blocking the signal, or radio interference from other electronic devices in your home.
DIY fix possible
Check that the internet router is switched on and functioning correctly.Ensure the Smart Interface plugged into the boiler is powered and has a light showing.Restart the Halo thermostat by removing and reinserting the batteries.Navigate to the advanced settings on the thermostat to re-pair the device to the interface.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like Connectivity Red — no call-out fees, no surprises.
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