Save £100 wiring a Nest (3rd Gen) to my boiler

alistone

Hey guys, my first post here but I'm hoping you can help me out. I'm an avid diy'er and my girlfriend is a terrible sleeper. Since the cold weather our boiler has been going mental turning on and off throughout the day/night. It's basically trying to keep up and the thermostat is a bit inaccurate (plus in a rubbish place above the radiator downstairs in our lounge).

So to try and solve these problems I bought a Nest 3rd gen thermostat. I am quite fine with DIY but haven't done much wiring and don't really know my way around a circuit board or diagram so wondered if you could help. I would really appreciate it! I'm happy with the replacing of my current thermostat with the nest, It's the heatlink that looks a bit scary.

So here's the breakdown:

- I have a combi boiler, it's an ideal independent C4 and situated upstairs in our bathroom (the power comes from below in the kitchen, which is the white cable in the picture)
- We have a single thermostat downstairs in our lounge
- I have a 3rd generation Nest with the heatlink
- I have 5 core flex cable
- I have included a picture of the boiler and the current connections below

I understand I need to run power to the nest and also connect it to the switch for turning on and off the boiler. I'm just not 100% sure which of the current setup I can remove (if I need to at all) and where to connnect the heatlink.

I would really appreciate the help and would happily offer a reward for such galantry

alistone

It won't let me post pictures as I'm a new member If you think you can help please give me a nudge and I'll send you the pics. Thanks!

alistone

Links to the images, just copy and paste into your browser please...

drive.google.com/open?id=1BJk3PWMiM9xfFwBZY2RK6nAGMuXgZVcw
drive.google.com/open?id=1GlZ6sZY3zKhOr90NeUCAFwHBiKQW_wck

Poppycat

alistone

Thanks so much @poppycat

Debbie_Savard

Can you double check the boiler model? Also is the white flex going to your existing thermostat?

Le_Kirk

Here are your pictures: -


https://drive.google.com/file/d/1GlZ6sZY3zKhOr90NeUCAFwHBiKQW_wck/view
https://drive.google.com/file/d/1BJk3PWMiM9xfFwBZY2RK6nAGMuXgZVcw/view

alistone

Yeah it says "Ideal Indpendent C24" on the front of the boiler. I'm struggling to remove the old thermostat atm but I'm pretty sure there is a wire going into that too as it controls all of the prorammes for the boiler.

benjus

Remove the brown wire linking the 2 rightmost terminals together.

Wire these two terminals to terminals 2 & 3 on the Nest heat link.

More information here if you're interested: https://www.freeboilermanuals.com/assets/pdf/ideal/Independent-C24-C30-C35-Installation-Manual.pdf (especially page 27)

Although I'm a bit confused as to how your current room thermostat is wired in, as I would have expected it to be connected to those two terminals.

alistone

Hmm interesting, I'll let you know when I remove it! But you think that should do the trick with the heatlink? So the "room stat timer" in the diagram in the manual you linked to? I imagine it also needs to be connected to live for power right?

I'll give it a try

antilles

Looks like it already has thermostat connected to me via the black and grey wires (they appear to have brown sheathing pushed over them unless I'm mistaken) - are those the thermostat connectors? They usually have a link between them which looks as though it's already been removed. So could it already have a thermostat connected? Looks like 5 core cable to me.

I'd bet those black and grey wires are connecting to a thermostat at the other end.