BoilerFaultCodesYour smart thermostat has lost connection with the boiler, causing it to enter a backup safety mode to ensure you aren't left without heat.
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: Failsafe active - Override and Failsafe only active when communication is lost between the Halo PRT and Smart Interface.
What causes this fault?
This fault occurs when the wireless connection between your thermostat and the boiler's interface is interrupted or lost. The most common reasons are dead batteries in the wall unit, electronic interference from other household devices, or the thermostat being moved too far away from the boiler.
This issue is slightly more common in winter when homeowners move furniture or festive decorations that can accidentally block the wireless signal between the thermostat and the boiler.
DIY fix possible
Check if the Halo thermostat batteries need replacing.Ensure the Halo thermostat is within range of the boiler and has not been moved behind a metal object.Restart your internet router if the problem persists.Press and hold the override button on the boiler interface for 3 seconds to attempt a manual reconnect.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like Override Green (flashing) — no call-out fees, no surprises.
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