Combi Boiler to hive active wiring help please!

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Hope you are all well.
Am trying to install a hive active in my flat with a combi boiler.
I have a Honeywell timer ST6100A with a frost room thermostat and a combiner's boiler 24i green star junior. The timer controls hot water and the room thermostat controls central heating. I need help wiring hive active instead of timer and hive active thermostat instead of room thermostat please! There is a spur of a 3amp fuse.

Here is the timer:
[GALLERY=media, 105731]IMG_20201220_065319 by AngelaBrady posted 23 Dec 2020 at 11:45 AM[/GALLERY]

Here is its wiring:
[GALLERY=media, 105732]IMG_20201220_065338 by AngelaBrady posted 23 Dec 2020 at 11:45 AM[/GALLERY]

Here is the thermostat:
[GALLERY=media, 105733]IMG_20201220_105333 by AngelaBrady posted 23 Dec 2020 at 11:45 AM[/GALLERY]

Please advise how to wire.
 
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The timer only controls one function, be it CH or DHW not sure, the thermostat also controls one function CH. With a combi boiler you can have control to DHW but unusual, and the wiring for Hive as title is very different to Nest talked about in text, and both Hive and Nest do twin and single channel versions.

For picture 1 of the timer back plate there seems to be a connector block behind the plate, and I would guess that connects the thermostat to the timer however guessing is not good enough.

But think first step is decide which thermostat you want to use. Hive single channel, Hive twin channel, Nest Gen 3, or Nest e.

You need to remove the programmer plate and take pictures showing what is behind the plate, I will guess three cables.

I think the 24i green star junior is a Worcester Bosch so no Opentherm, but it may be able to use one of the Worcester Bosch specials.

And also you have to consider do you have the skill? Seem to have seen these pictures before, so assume it is an on going problem. I read up on Bosch Worcester to get my mothers gas boiler working better, and it seems the year is important as latter versions had more options.
 
Many thanks for your replies.
I am trying ti work out which thermostat works for my system.
I a going to take another picture of my timer and test that the cables connected to my timer from the thermostat are 12volts to be able to connect nest 3rd or to a hive.
Thanks for your patience and support
 
You have a 230/240vac thermostat, so therefore it’ll be 230/240vac outputs. What’s wrong with the existing setup?
 
You have a 230/240vac thermostat, so therefore it’ll be 230/240vac outputs. What’s wrong with the existing setup?
Thermostat has only 2 wires, so unknown if 230 volt or 24 volt, as far as aware no 12 volt option on that boiler, and the programmer is volt free contacts so again nothing to say 230 volt or 24 volt.

Although Nest Gen 3 uses 12 volt, this is thermostat to heat link and has nothing to do with connection to boiler. Nest Gen 3 and Nest e are both volt free contacts except when using OpenTherm, Hive single channel is volt free, duel channel is not.

It is likely all 4 could be used, but as it stands don't know.
 
Didn’t think it would work on 24v :oops: however it’s a Greenstar Junior, so pretty certain it’ll be mains voltage :whistle:
 
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