In my opinion it is a load of rubbish. If they knew that then they could have omitted the one directly below the boiler and fitted just the one under the stairs.
Still don't understand how that would work. Maybe BG know something we don't about those receivers. Either that or BG have access to a special repeater version that is not available to the rest of the trade
They have been to my friends today and said that the receiver under the stairs is simply a repeater from the one directly below the boiler as when they tested the found just one unit not to have satisfactory comms from the room stat. No seperate zonings.
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