Another Nest Themorstat (3rd gen) question

[miguew]

Hi all,

I want to replace my current thermostat (pictures below) with the Nest Thermostat, but wire labels don't match.

My boiler is Worcester Greenstar 24i Junior combi boiler, which is on the back of the wall where the thermostat is.

Any help is massively appreciated on how to set it up. Cheers!

 

[CBW]

I’m not sure what you mean by the wire labels don’t match, you only have live and switched there. You need to provide a permanent live and permanent neutral. Opening the case on that boiler forms part of the combustion circuit and must be done by someone who carry out safety checks afterwards.

 

[RandomGrinch]

Your simplest option may be to exchange your Nest for a battery powered Nest thermostat E or similar.
The Nest E heatlink would then simply replace your current thermostat on the wall, without any additional wiring (although it may be straightforward to gain a live and neutral directly from the boilers FCU?).

...also, ideally, that blue wire should be sleeved in brown; denoting it as a live wire and not a neutral!

...and remember to set the timer on the boiler to permanently 'On'!

 

[ianmcd]

Agree nest E is your best bet for what you are trying to do

 

[miguew]

Thanks all. Looking at the Nest E it definitely looks like it would be much simpler given what I currently have!

 

[ianmcd]

Thanks all. Looking at the Nest E it definitely looks like it would be much simpler given what I currently have!

definately your best solution, you wont need to open the boiler, but remember the existing timer must be set to constantly on , the nest E will over ride it