Evohome BDR91 and Powermax HE150/Drayton LP722 Wiring

[steve.mack]

After some guidance, I asked a similar question in another thread but now I'm onto specifics, we've just had all our rads changed and I've got all these Evohome TRVs to fit now. I couldn't find a local expert on evohome. The one guy I found who had some knowledge, said he's never seen our boiler before and didn't want to touch it

Hence I'm a bit stumped though with how to wire this BDR91.

We currently have a Powermax HE150 Storage boiler (Combi but not a combi, not a lot of people seem to know them).

This is linked to a drayton lifestyle LP722 and a honeywell thermostat in our hall (I assume the stat connects to the LP722, I've not investigated it that much). We want to keep the hot water connected to the drayton for now as the boilers getting changed next year or following year so don't want to have to buy the evohome hot water kit.

 

[steve.mack]

As an alternate idea, do I just strip the Honeywell thermostat off the wall and put the BDR91 there?

IMG_8296

• steve.mack
• 2 May 2019

IMG_8297 (1)

• steve.mack
• 2 May 2019

 

[steve.mack]

Any ideas anyone?

 

[ianmcd]

As an alternate idea, do I just strip the Honeywell thermostat off the wall and put the BDR91 there?

IMG_8296

• steve.mack
• 2 May 2019

IMG_8297 (1)

• steve.mack
• 2 May 2019

You could put the BDR where the thermostat is but you would have to run another cable to it as your existing is battery powered and the BDR requires a permanent Live & neutral as well as the switching wires

 

[steve.mack]

You could put the BDR where the thermostat is but you would have to run another cable to it as your existing is battery powered and the BDR requires a permanent Live & neutral as well as the switching wires

I thought the batteries were a ‘backup’ as the backing plate says 24-230v on it, or is that referring to the potential voltage in of the wires coming in?

I’m probably best wiring it at the drayton 2 channel controller... will the thermostat connect to this or run to the boiler?

 

[ianmcd]

No the 24v 240v means that the switching can be either, the stat is mains powered the batteries control the thermostat,I would put the BDR next to the LP722 or next to the powermax if easier, the existing thermostat will have two wires running to it, if you can identify these wires then connect them to the BDR switching terminals, then supply a L&N to the BDR and you are good to go

 

[steve.mack]

No the 24v 240v means that the switching can be either, the stat is mains powered the batteries control the thermostat,I would put the BDR next to the LP722 or next to the powermax if easier, the existing thermostat will have two wires running to it, if you can identify these wires then connect them to the BDR switching terminals, then supply a L&N to the BDR and you are good to go

Ah ok, sounds pretty easy, think I can cope with that putting it next to the LP722 and then leave the LP722 to permanently on for the heating. Lets see how I get on