Replacing Dual Zone Honeywell with Hive

24 Jul 2018
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United Kingdom

I wondering if anyone can help me. I have moved into a new Bellway build and I'm looking to replace the current dual zone Honeywell system with a Hive system.

Currently there is a Honeywell ST9100c under the boiler. In the living room and on the top floor there are CM707 units. The top floor thermostat controls all the bedrooms and the livingroom one controls the downstairs.

I have purchased a Hive Active Heating and Hot Water Thermostat and a Hive Active Heating Multizone Additional Smart Thermostat.

I've attached a screenshot of the wiring behind the ST9100c.

Am I right in thinking I will need to purchase an additional multizone smart thermostat as I have 3 units? I'm pretty sure I understand how to replace the one in the kitchen but I would have expected there to more wiring behind the existing unit as there is multizones in the house.

Any help would very much appreciated.

Thanks in advance,


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You need to find the wiring centre in your cylinder cupboard and wire everything into there, as well as potentially altering the wiring you've shown. Worth noting that Hive is the least energy-saving of all the Internet-enabled thermostats and is therefore unlikely to improve over your current setup
Thanks Muggles, I really appreciate the help. It's taken me while to get round to looking at this again. The reason why I bought Hive was that it was on offer and I'm away quite a bit with work and forget to turn off heating/hot water.

I've managed to find all the cabling in the cylinder cupboard, WOW.

I've drawn out diagram of how every thing is connected up.

The connection block on the right appears to be the Live/Neutral/Earth

I have both a single channel receiver(upstairs heating) and a dual channel receiver(hot water/downstairs heating)

For the dual channel receiver I need to identify which wires I should connect to:
1 - Hot water off
2 - Heating off
3 - Hot water on
4 - Heating on

For the single receiver I need to identify which cables I should connect to:
1 - Common
2 - Heating off
3 - Heating on

There are 4 cables running into the cylinder cupboard. I've identified 2 as thermostats as I can feel the pipes that connect to different valves getting hot, but the other two I'm not too sure where they go.

Any help you can provide is much appreciated.



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All sorted, was easier than I thought. Just connected up only the heating/hotwater on to the three valves. Still need to remove old wiring to the redundant hot water panel as looks like it's wired directly into boiler but will look at that another day.

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