Nest - again sorry from ESI

[Finn-uk]

Hi

I’ve bought a new build (I know!) and it has two heating zones controlled by ESRPT5 thermostats.

the motor valves are in a cupboard upstairs wired into a white box on the wall. I opened the box today to look at the wiring for moving to nest and found this!

DF96AD85-D114-466F-A247-41FBA5323223

• Finn-uk
• 31 Dec 2019

215DD997-B7FF-45CD-B198-AAD3FCF894D4

• Finn-uk
• 31 Dec 2019

I’m guessing that the thermostats are mains wired and end up here in this mass of wires and junction boxes.

do you think it’s possible to install my heat links in this location? Will have to rethink positioning of thermostat as I was hoping just to be able to swap it out!

thanks

Anthony

 

[ianmcd]

I’m guessing that the thermostats are mains wired and end up here in this mass of wires and junction boxes.

No the The thermostats are 12v dc powered, the heat links are mains wired and will go next to that wiring centre, the heat link controls the valves and the valves turn the boiler on and off

 

[muggles]

It's not pretty, but I've seen worse...

Yes your heat links should wire into there. You just need to work out which are the thermostat wires but that should be easy enough to do. Once you've got those, they go to T1 and T2 in your HLs

 

[Finn-uk]

No the The thermostats are 12v dc powered, the heat links are mains wired and will go next to that wiring centre, the heat link controls the valves and the valves turn the boiler on and off

sorry, I meant I think the existing esi thermostats are mains wired, so will have reconsider the position of the new nest thermostats (12v)

 

[muggles]

You can use the existing mains wires to power your Nest thermostats, you just need to disconnect them from the mains and connect them to the Heat Links instead

 

[Finn-uk]

Is it easier to just remove the valve wires and move them across to the HL and run new L&N to the existing junction boxes from the HL?

 

[ianmcd]

you only need a live wire from the HL NO terminal to the brown wire on the corresponding valve and a live and neutral to power the heatlink

 

[Finn-uk]

you only need a live wire from the HL NO terminal to the brown wire on the corresponding valve and a live and neutral to power the heatlink

I’ll also need to remove the wires from the thermostat and connect to T1 and T2?

 

[ianmcd]

I’ll also need to remove the wires from the thermostat and connect to T1 and T2?

yes of course but with your set up is very easy to do

 

[Finn-uk]

yes of course but with your set up is very easy to do

it’s just finding the correct incoming cables! Working out which of the three are the two thermostats (and which is up and down stairs) and the cable to the boiler (but that should be the one connected to the orange wires I presume!)

And then I need to look at the wiring behind the existing thermostats as I think they will also have a mains supply!

 

[ianmcd]

no all the valves orange wires will be linked together and all the grey wires will also be linked together , you are only interested in the individual Brown wires for each valve

 

[Finn-uk]

no all the valves orange wires will be linked together and all the grey wires will also be linked together , you are only interested in the individual Brown wires for each valve

hi, yes I understand this bit for the valves, it’s the wires coming in from the thermostats that confused me. I can’t leave them wired in as they are because I need to remove the old thermostats, I just need to find the appropriate cables and rewire them to the T1 and T2 so I can mount the nest thermostats. I was thinking that the orange wires will help me identify the cable from the boiler and rule that one out!

Thanks for your continued help.

ta

 

[ianmcd]

No the orange and grey wires are simply a switch all orange and all grey wires must remain as they are, what you are trying to do is possible, but to be honest not a DIY task, as you need to know what you are doing, could be done , but not as straight forward as you think

 

[Finn-uk]

All in and working. It was relatively simple I was just over thinking it! Thanks to all who helped!