Honeywell st9100c (replacing with Hive)

[GMan51]

Hello everyone,

I aim to replace the the st9100c with the Hive active heat single channel (no water).

Tomorrow I will look at the wiring on the existing st9100c - any ideas what I should expect and do you think it should be a simple direct swap? N, L, 1, 2, 3, 4? blue, brown.. what colours should be others be? Thanks, Gareth.

 

[stem]

The wiring is slightly different, the wires you need will be there, but one will need re-positioning.

The Honeywell ST9100 is wired as below:

And the Hive Single Channel

The wiring colours used would be at the discretion of the original installer and the materials available to them. Some poor installers will use blue wires which are normally used for neutral as live wires without identifying them as such by adding a brown sleeve. So, it is not possible to advise regarding the existing wiring colours. Where they go will identify what they do.

From the above diagrams, you will see that terminals N, L and 1 are the same for both devices. If there is presently a link between L and 1 that should be retained, but do not add one, if there isn't one there already.

The remaining wire in the ST9100 terminal 4 (On) will go to the Hive terminal 3 (Heating on)

The ST9100 is only a timeswitch, but the Hive is a combined thermostat and timeswitch. You haven't mentioned any existing room thermostat, so I would assume from that, that you don't have one. In that case the above is all you need to do.

If you do have an existing room thermostat, then it should be decommissioned properly, which will involve removing it and making a minor wiring modification, to prevent it interfering with the operation of the Hive.

 

[GMan51]

Stem, thank-you very much for your comprehensive answer!

You are correct in saying that my current set up does not have a thermostat attached so the wiring should be as you indicate.

Many thanks again.

Let's now hope that the Hive device works with the boiler that I have and there aren't any compatibility issues. The other thing that I'm slightly concerned about is the distance from the receiver to the HUB (a few solid walls), but I think I can purchase a Hive booster to hopefully sort out that issue.

I'm aware that Hive is designed more for domestic properties, not a church as such, but hoping it will still work. I did get a cost for a WiFi commercial heating set-up, but the price was over £2000 for just one boiler.

Gareth.

 

[stem]

I'm aware that Hive is designed more for domestic properties, not a church as such

I have installed a few Hives and Nests and helped others to do so, but don't have either myself. Being able to operate my heating remotely doesn't offer me any advantages. However, I can see the advantage of being able to remotely control the heating in a building such as a church.

Usually large premises require several zones to enable a comfortable temperature evenly though. I worked on an installation in a church hall where the sole thermostat was located in the main room. When there was a large function on, the heat of the 100 or so occupants raised the temperature and turned off the the entire heating leaving all of the auxiliary rooms cold, so we formed two zones, one for the main area and a second one for the auxiliary rooms.

 

[GMan51]

One final question.. the boiler manufacturer has said that a wifi heating unit (such as Hive) can only be installed on the boiler if it is voltage free compatible. Is the hive (heat only) voltage free?
Thanks again.

 

[stem]

Yes, it's only the Single Channel version of the Hive that has voltage free contacts 'Common' and 'Heating on' (Terminals 1 and 3)

 

[GMan51]

I'm pleased to report that the re wiring was very simple and it all works brilliantly! Thanks again for your help.

 

[Robin Davies]

F.A.O. Stem

Hi there, I have read with interest the guidance you have given on changing to a Hive unit from Honeywell. I am in a similar position, but a CM927 unit. Trying to do the installation of a single channel Hive receiver to connect to my Worcester Greenstar 30Cdi combi and 'talk' to the wireless thermostat. I am nearly there in so much as I have linked the easy wires from receiver to boiler (i.e. live, neutral and earth). There are, of course, a further two wires; one to send the live supply out to the receiver (from boiler) and the other to return to boiler to bring it on.

On the BDR91 Honeywell receiver they ran from A to T1 (or Live supply, Ls) on the boiler and the other from B to T2 (or Lr on the boiler). According to the boiler manual (and confirmed by a technical guy at Worcester), these two connections are 230V.

I have connected T1 to slot 1. (common) and T2 to slot 3 (Heating On) on the Hive receiver back plate, but no joy. Getting no status light or anything, all 'dead'. Would you have any suggestions?

According to the Hive website:

Our receivers are supplied from mains (the permanent live and permanent neutral connections). The single channel receiver has “dry contacts” or “zero volt contacts”, that means it acts like a switch connecting the signal input terminal (shown as “Common” in our install guide) to the normally open (Heating on) or normally closed (heating off) output terminals. This single channel receiver can switch low voltage or mains voltage boiler control signals. The voltage to be switched connects to the Common terminal.

So I think I have done right. Hope you can help

Robin

 

[stem]

The Hive simply replaces the BDR.

The wires just move across from the BDR to the Hive terminals that have the same function. There is no need to do anything at the boiler end. You are simply exchanging one thermostat receiver for another.

They can be wired up in several ways, according to the preference of the original installer.

So, if there were 4 wires used originally (excluding earth) at the BDR they connect to the Hive as follows:

Wire in BDR N goes to Hive N
Wire in BDR L goes to Hive L
Wire in BDR A goes to Hive 1 (Common)
Wire in BDR B goes to Hive 3 (Heating on)

If there were only 3 wires used originally (excluding earth) at the BDR they connect to the Hive as follows:

Wire in BDR N goes to Hive N
Wire in BDR L goes to Hive L and also to Hive 1 (Common), you will need to add a link wire between the L and 1 terminals
Wire in BDR B goes to Hive 3 (Heating on)

 

[Robin Davies]

Hi stem,
Just read your reply to me, thank you. As I mentioned in my first post, I have done exactly as you specify in the first example (i.e. where 4 wires were originally used), but nothing is happening. When I power back up, the status light on the receiver should flash amber, but I am getting nothing at all..would it be worth trying a swap around of the original BDR A and B wires, i.e. put BDR A into Hive 3 and BDR B into Hive 1?

 

[stem]

If there were four wires in the BDR L, N, A and B, it was working correctly before you started, you have moved the wires as below, and changed nothing else anywhere; then that is correct, you have simply exchanged one receiver for another like for like. N & L are a 230V supply, and A&B [BDR] and 1&3 [Hive] are simply an on/off switch. The two terminals are connected together internally when the heating should be on.

All I can suggest is that you check the wires are securely held in the terminals and contact is with the wire not the insulation and that the fuses are in order. It sounds like the Hive isn't getting any power if no lights are appearing. So the N & L would be a good place to start.

You haven't mentioned any other controls and I wouldn't expect any, as you have a programmable thermostat already. However, If there is some existing time control somewhere ie in the boiler, that will need to now be set to be permanently 'on'

Wire in BDR N goes to Hive N
Wire in BDR L goes to Hive L
Wire in BDR A goes to Hive 1 (Common)
Wire in BDR B goes to Hive 3 (Heating on)

 

[Robin Davies]

I don't have any controls; the original set up was just the Honeywell BDR receiver and the wireless thermostat. The boiler is coming on fine so it would suggest that the L and N coming from my fused switch - via Hive receiver - to boiler are sound. So why, I wonder, is the Hive receiver seemingly not getting any power??

 

[Robin Davies]

Finally...success!! Just decided to take the front cover off the receiver and carefully re-fit it to the back-plate, switched power on and after a few seconds got the amber flashing light. I guess I now need to get it paired up with the thermostat. Is that pretty straightforward?

 

[Robin Davies]

Everything seems to be up and running. I've noticed straight away, however, that the time displayed in the top left of the thermostat is not right. Is it possible to manual alter? Be aware that I don't have a hub, just receiver and wireless stat.

 

[stem]

Glad to hear you got the wiring sorted, I thought it would be a connection problem. Unfortunately I've never installed a Hive without the hub, it's always come as part of the kit, and to be honest I thought it was an essential component of it. So, unfortunately, I can't help you with that aspect.