Installing Nest Thermostat 3rd Gen

fayraz

Hi,

Just after some advice I have a standard combi boiler with a wireless thermostat which only controls the heating and now need to connect the heatlink.

My current wiring:

https://photos.app.goo.gl/XHLgB9zugeEg8bXL8

https://photos.app.goo.gl/EFjTs1Z9ndM9gnwV9

I have 2 cables, one from the fuse spur which goes to L, N and E and then another cable from the boiler which goes to L, N, E, 1 and 3.

In the heatlink according to the Nest diagram I need to connect both cables to the L, N and E and then the 2 extra wires which go to 1 & 3 on the Nest 1 needs to go to 2 and 3 goes to 3.


Forgot about that, just what I was saying above is this correct if I wire it like this:

So question is.....I need to connect both cables to the L, N and E and then the 2 extra wires from the boiler currently go to 1 & 3, on the Nest heatlink do I need to connect 1(OLD) to 2(NEST) and 3(OLD) to 3(NEST)?

Thanks.


Hope this make sense?

Thanks.

mrprosser

It all depends on your boiler, which is why Nest recommend professional fitting.


I had a Nest on my old boiler (a Ravenheat) and the wiring was totally different on my new Bosch boiler

Tranquil

I would recommend getting a professional installer. It’s not actually that expensive if you get someone who knows what they are doing (look at nest website for approved installers). Much less hassle down the line to just get it installed correctly rather than fix numerous problems!

bob_a_builder

Sound right to me - although I've not checked the pin numbers of the Nest you quote

But as long as your old 1 & 3 are connected to the Common and NO contacts of the heat link. all should be good

You are just replacing one set of switch (relay) contacts in the wireless stat for the set in the heat link (plus you need the LNE to provide power to the heat link)

I chose the Nest E where the heat link box is battery powered and is a bit cheaper since only controls Heating and not Hot water