Hello there,

I am installing my Honeywell EvoHome in our new house and it should be easy. All I need to do is replace the Hallway Thermostat (Honeywell T6360B) with the Wireless Relay box (BDR91). However, I am not sure which wires from the old thermostat go into which places in the BDR91. As shown in the photo the hallway thermostat has four wires (inc the earth) and these go into locations 1, 2 and 4. I can work out which ones go to N and L in the BDR91, but do I need a 'switching live' (i.e. a separate wire from L to A), or where does the thrid wire from the hallway thermostat go into?

We have an Ideal Logic Heat 30 boiler, not a combie as we have a separate hot water tank.

Any help will be super appreciated.20211002_152336.jpg

Cheers, Stewart