Replacing existing Honeywell wired thermostat and hot water (Y plan) with Heatmiser smart control and possible wireless thermostat

[Samsg30]

Hi,

I have a Honeywell timer and room thermostat with one zone for CH and one for HW under Y plan mid position valve.
I am looking to replace it with Heatmiser control so that I can control the heating and hot water remotely and use the geo location feature that turns off CH if no one is around.
I am kind of overwhelmed with the choice available with Heatmiser and narrowed down on two options below. But I am not sure which will be the suitable option for diy I.e. without fiddling with 10 port junction box

Option 1: Heatmiser neohub mini v2 with neoAir wireless thermostat v3.
This would be my preferred choice but I am not sure how to replace the existing wired thermostat with the wireless one i.e. making the wired thermostat redundant so wireless thermostat can be put into a suitable location.
Do I need to fiddle with 10port or just replacing timer with neohub mini is good enough leaving the old wired thermostat at 0 or highest temp.

Option 2: (less preferred): RF switch v2 with wired slimline RF thermostat and neoHub v2
Would this will be like for like replacement i.e. replacing wired thermostat with new slimline wired and programmer/timer with RF switch. neoHub will provide all the intelligence of geo location etc.



Thanks

 

[CBW]

Both of those are wireless versions, so either way you will likely need to alter the 10 way strip in the wiring center

 

[Samsg30]

Oh is it. I thought option 2 is wired thermostat which talks to RF controller wirelessly.
I am not newby with diy or electric as such but never fiddled with 10way junction or CH electrical.
Is there some sort of info that can precisely tell me which wires to alter as I can't see enough info regarding this in the Heatmiser product manual itself

 

[CBW]

Oh is it. I thought option 2 is wired thermostat which talks to RF controller wirelessly.
I am not newby with diy or electric as such but never fiddled with 10way junction or CH electrical.
Is there some sort of info that can precisely tell me which wires to alter as I can't see enough info regarding this in the Heatmiser product manual itself

Apologies, must have been looking at the wrong version. Looks like that version would work, although you’d need to add live links between L and Common.

 

[RandomGrinch]

The Heatmiser Neohub Mini HW should be able to replace the ST6400C - if you are happy to take it off of the backplate, we should be able to confirm which wires you need to connect. It may look something like this:

As @CBW states above, some link wire will be needed on the Neohub to connect L to C1 and C3.

If you don't mind the old thermostat remaining in place, just turn it to maximum; there will be no need to touch the wiring centre - that can be a job for another day!

 

[Samsg30]

I think you are right. Looking again at the product compatibility, both are actually wireless thermostats. I don't know why they have Slimline RF wireless and NeoAir wireless thermostats.. can't understand the difference other then the compatibility.. they have so many products to choose from.
I am attaching the product description and the installation guide of all 4 products i.e. slimline RF v3 thermostat + RF switch v2
And
NeoHub mini + NeoAir Thermostat

So, if both are wireless thermostat and I have to deal with 10 port junction box, any idea what will it need to install NeoHub mini with NeoAir thermostat?

 

[RandomGrinch]

So, if both are wireless thermostat and I have to deal with 10 port junction box, any idea what will it need to install NeoHub mini with NeoAir thermostat?

As above, no need to mess with the junction box, just swap the ST6400C for the neoHub Mini and mount the battery operated neoAir to a wall of your choice.
Pair according to pages 16 of the neoAir manual.

 

[Samsg30]

The Heatmiser Neohub Mini HW should be able to replace the ST6400C - if you are happy to take it off of the backplate, we should be able to confirm which wires you need to connect. It may look something like this:

View attachment 312939
As @CBW states above, some link wire will be needed on the Neohub to connect L to C1 and C3.

View attachment 312940

If you don't mind the old thermostat remaining in place, just turn it to maximum; there will be no need to touch the wiring centre - that can be a job for another day!

Just read your reply after posting mine. I am happy to leave old thermostat with turned to max settings. Attached is the picture of existing controller and neoHub Hw mini diagram. I have Y plan though instead of S plan shown in the neohub diagram but guess it won't make a difference.

 

[RandomGrinch]

It's now considered unaceptable to use a green/yellow wire for anything apart from an earth connection. Although the regs aren't retrospective, ideally you should have a five core + earth flex.
At the least, cover the green/yellow wire with brown sleeving.

Apart from that, I believe...

L to L
N to N
Link wire between L, C1 and C3

1 to NC3
3 to NO3
4 to NO1

 

[Samsg30]

Thank you very much for your quick and detailed response.
It looks like the old controller doesn't have earth coming in so hopefully that's not a problem? I'll put brown or red tape on the green yellow cable to mark it appropriately. Anyhow, during renovation, all this will be replaced so hopefully they should follow the latest standard.
Just to confirm my understanding on "link cable between L, C1 and C3 means making a w type wire connection between these three points so they are like permanent live? (As shown with the red ink in the picture?

 

[RandomGrinch]

It looks like the old controller doesn't have earth coming in so hopefully that's not a problem?

It shouldn't be a problem - the ST6400C is double insulated, and althought I can't confirm it from the internet, it is highly likely that the neoHub Mini will also be DI.

I'll put brown or red tape on the green yellow cable to mark it appropriately

Brown please!

Just to confirm my understanding on "link cable between L, C1 and C3 means making a w type wire connection between these three points so they are like permanent live? (As shown with the red ink in the picture?

Yes, exactly

 

[Samsg30]

Thankyou very much for your kind response. It does give me confidence to order the product and go with the installation.
I suppose the old thermostat (set to highest temperature) will be overridden with whatever the wireless thermostat will tell the controller. So if timer is on and wireless thermostat is set to 20c, CH won't come on unless room temp is below 20 even if wired thermostat is set to 30C.

 

[RandomGrinch]

I suppose the old thermostat (set to highest temperature) will be overridden with whatever the wireless thermostat will tell the controller.

Yes.

...and if you do have the confidence to delve into the wiring centre and have a go at permanently disconnecting the thermostat - Follow the switching wires from the stat (probably those connected to terminals 1 and 3) back to the wiring centre and simply link them out (probably terminals 4 and 5)..

Good luck!

 

[Samsg30]

Thanks.. really helpful

 

[Samsg30]

@RandomGrinch @CBW I spoke to Heatmiser support today about some of the features and what they actually suggested to go with the wired thermostat to control HW (called NeoStat HW V2) and a separate wired thermostat for CH (called NeoStat v2) , both of which can connect to a wireless headphones hub to set the timer, remote control features and geo location.

So I am back to the original question on how to wire it please.

Attached are the pictures of existing honeywell timer and dial thermostat to control HW and CH. I am also attaching the wiring guide of NeoStat HW for 3 port valve. But looking at the attached pdf of CH thermostat, not sure which wiring diagram to use.
Any help is appreciated.

Existing controller picture

Existing thermostat wiring

Wiring diagram of new NeoStat HW controller for 3 port valve (and pdf)

Attached pdf of both NeoStat for CH and HW