Wiring for Hive to replace Honeywell ST9400c and BDR91

[jw80]

Hi all

I would like to replace my Honeywell with a Hive to control both the heating and hot water (tank) and I was after some advice on the wiring. The current set up is like this

Hive2

• jw80
• 23 Nov 2020

Hive1

• jw80
• 23 Nov 2020

and then the BDR91 has a wireless link to a thermostat. How do I remove the BDR91 from the set up? And am I also right to say that on the ST9400c it's the following at the moment?
1 - HW off
2 - CH off (no used)
3 - HW on
4 - CH on

Many thanks in advance
Jamie

 

[stem]

The ST900c and the Hive Dual Channel Receiver as you can see below, have exactly the same connections. So the existing wires in terminals N, L, 1, 3, & 4 move from the Honeywell to the Hive, like for like.

Regarding the BDR91:

1. The wires from the BDR91 should be traced back from the thermostat to their origin. When you find their origin, the brown and blue wires from N & L should be disconnected and removed.

2. Note where the two black wires from A and B originate from and then remove them also. At this point all of the wires going to the BRD91 will be disconnected, and the BDR can be removed.

3. Now insert a wire link to join together the two terminals, where the two black wires you just removed came from so that the terminals are electrically connected.

Or if that's too difficult, fix a junction box where the BRD91 is now, put the brown live wire in one terminal on its own, the blue neutral wire in a terminal on its own, and the two back wires in a third terminal together.

 

[CBW]

Hi Jamie,

That BDR looks like it’s near the programmer, so to remove should be straightforward, then copy the wiring configuration over.

Edit: Stem beat me to it.

 

[jw80]

That's fantastic, thanks both. Got the Hive on order so will install at the weekend.

These forums and the kind folk who post on them never cease to amaze me