What wire for nest thermostat?

[Mr Sparkle]

I want to wire the Nest thermostat to the heat link

Apparently the thermostat works on 12v

Anyone know what wire do I need?

FYI the heatlink has already been connected to the boiler

 

[CBW]

You can use existing thermostat wires if available, if not and you want to run some, Ive been told it should be this: https://www.cef.co.uk/catalogue/pro...rol-flexible-cable-cut-length-sold-by-the-mtr or if that doesn’t work, use the usb cable?

 

[ericmark]

Any pair of wires will work, it does not seem to mind, mine uses some 1 mm² twin and earth and triple and earth and at least two joints and works A1.

 

[Mr Sparkle]

You can use existing thermostat wires if available, if not and you want to run some, Ive been told it should be this: https://www.cef.co.uk/catalogue/pro...rol-flexible-cable-cut-length-sold-by-the-mtr or if that doesn’t work, use the usb cable?

Superstar you are. Thank you.

Any pair of wires will work, it does not seem to mind, mine uses some 1 mm² twin and earth and triple and earth and at least two joints and works A1.

That's interesting

So just so that i'm clear. You can power the nest thermostat by running some 1 mm² twin and earth from the T1 and T2 connections on the heatlink to the thermostat itself?

And it doesn't matter which way round the the coloured blue and brown wires are?

 

[CBW]

So just so that i'm clear. You can power the nest thermostat by running some 1 mm² twin and earth from the T1 and T2 connections on the heatlink to the thermostat itself?

And it doesn't matter which way round the the coloured blue and brown wires are?

Yes and no it doesn’t matter which way around.

 

[SFK]

I tend to put the 12V on the brown wire and 0V on the blue wire.
And I like to write 12V on the outside of the cable at both ends to remind me in future (although always best to check not live before touching).
SFK

 

[Adrian Faithfull]

Sorry to jump on your thread, i too have just had a new central heating system fitted.

We have purchased 2 nest thermostats as we have 2 zones. the Plumber has installed the heatlinks but wants to charge £100 to run the 12v cable to the 2 thermostats which im pretty sure is something i can do. The recommended cable above is currently out of stock at CEF, would this one be suitable?

https://www.screwfix.com/p/time-219...FjYneImDyJJqe03437EaAjPJEALw_wcB&gclsrc=aw.ds

or could you recommend another suitable product?

 

[RandomGrinch]

Sorry to jump on your thread, i too have just had a new central heating system fitted.

We have purchased 2 nest thermostats as we have 2 zones. the Plumber has installed the heatlinks but wants to charge £100 to run the 12v cable to the 2 thermostats which im pretty sure is something i can do. The recommended cable above is currently out of stock at CEF, would this one be suitable?

https://www.screwfix.com/p/time-219...FjYneImDyJJqe03437EaAjPJEALw_wcB&gclsrc=aw.ds

or could you recommend another suitable product?

Yep,
That wire should be fine.
The recommended wire has shielding that can suppress interference; this has occasionally been reported as a problem for Nests.
However, my Nest is run on exactly the same cable as your choice, with no issues!

As above, it is good practice to label the cables as 12V DC, to differentiate them from mains cables.

 

[ericmark]

So just so that i'm clear. You can power the nest thermostat by running some 1 mm² twin and earth from the T1 and T2 connections on the heatlink to the thermostat itself?

And it doesn't matter which way round the the coloured blue and brown wires are?

Correct

We have purchased 2 nest thermostats as we have 2 zones.

As far as I am aware Nest as yet in UK does not link to heat sensors. In USA it does, but not in UK.

It does depend on the boiler, as far as I am aware only EPL do thermostats which can be set to master or slave and you can have up to 10 thermostats linked together working the boiler using opentherm and open and close zone valve with digital on/off.

You can have as many thermostats as you want in parallel using simple on/off, but that does seem to defeat the whole idea of a modulating boiler.