Nest thermostat e installation

[Evans-Gibson]

Hi I want to replace my current Honeywell CM927 with a Nest e. I'm having some trouble identifying the correct wiring. Please see pictures of current receiver I want to replace with the nest e heat link. Any advice and instructions would be greatly appreciated.

 

[James]

Install the nest app, it has step by step instructions on how to fit it as part of the setup.

If unsure, leave it in the box and call a local electrician.

 

[Evans-Gibson]

Thanks for the reply I'm having trouble identifying the correct wires using the nest app instructions. I was hoping someone had done a similar swap and could help me identify the correct two wires from the picture.once again any help would be appreciated.

 

[Sparks30]

Thanks for the reply I'm having trouble identifying the correct wires using the nest app instructions. I was hoping someone had done a similar swap and could help me identify the correct two wires from the picture.once again any help would be appreciated.

nest thermostat requires 12v dc.
take brown and blue and connect to t1 and t2 on nest receiver
if you have a combi boiler it isnt too hard but if you have a system boiler then it is a bit more complicated.
see manual aswell.

 

[James]

nest thermostat e is battery powered.
blue wire is not required.
if you cant identify the correct live feed and call for heat wires and understand where to connect them, i strongly suggest you find either a nest pro installer or a local electrician that is used to heating controls.

If you get it wrong, it is possible to have a £200 thermostat that is only of use as an ornament because the electronics have been destroyed.

 

[Evans-Gibson]

Yes it is nest thermostat e that's battery powered so was confident blue and brown wires were not to be used. Thanks for the advice though I think I might call a electrtion.

 

[davesparks]

nest thermostat requires 12v dc.
take brown and blue and connect to t1 and t2 on nest receiver
if you have a combi boiler it isnt too hard but if you have a system boiler then it is a bit more complicated.
see manual aswell.

Nest thermostat e does not require a 12v supply and does not have a receiver.
Following your advice to connect brown and blue will result in a short circuit and damage to the nest thermostat e

 

[Evans-Gibson]

Nest thermostat e does not require a 12v supply and does not have a receiver.
Following your advice to connect brown and blue will result in a short circuit and damage to the nest thermostat e

I opened up the old reciver and Blue connected to N (not needed for thermostat e) brown connected to L. Then a small piece of black wire looped going from L (next to brown over to A) then finally a grey wire connected to B.

 

[UNG]

I opened up the old reciver and Blue connected to N (not needed for thermostat e) brown connected to L. Then a small piece of black wire looped going from L (next to brown over to A) then finally a grey wire connected to B.

So L and B wires are the ones you need and a block on the blue wire

 

[Evans-Gibson]

So would I be correct in saying Brown is C for nest thermostat e and the grey is no ?

 

[UNG]

So would I be correct in saying Brown is C for nest thermostat e and the grey is no ? View attachment 59938

That's it you have got it right

 

[Sparks30]

Nest thermostat e does not require a 12v supply and does not have a receiver.
Following your advice to connect brown and blue will result in a short circuit and damage to the nest thermostat e

yes it does and does have a heat link where 12v dc is supplied from or use usb cable supplied with it.

ive installed loads of and have in my home too So i know what im talking about.

no it wont, brown on t1 blue on t2 on heat link, same on stat
Done
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nest thermostat e is battery powered.
blue wire is not required.
if you cant identify the correct live feed and call for heat wires and understand where to connect them, i strongly suggest you find either a nest pro installer or a local electrician that is used to heating controls.

If you get it wrong, it is possible to have a £200 thermostat that is only of use as an ornament because the electronics have been destroyed.

wonder what battery you for nest thermosta?

 

[Evans-Gibson]

So L and B wires are the ones you need and a block on the blue wire

Followed this advice and all is working perfectly, thanks to everyone who offered help and advive.

 

[UNG]

yes it does and does have a heat link where 12v dc is supplied from or use usb cable supplied with it.

ive installed loads of and have in my home too So i know what im talking about.

no it wont, brown on t1 blue on t2 on heat link, same on stat
Done
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wonder what battery you for nest thermosta?

You clearly have not fitted any Nest E thermostats as there are only 2 connections on them (see post #12) and power is supplied from 2 AA batteries, if you had fitted them you would know this and not be dissing other peoples posts

 

[davesparks]

yes it does and does have a heat link where 12v dc is supplied from or use usb cable supplied with it.

ive installed loads of and have in my home too So i know what im talking about.

no it wont, brown on t1 blue on t2 on heat link, same on stat
Done
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wonder what battery you for nest thermosta?

You are describing a nest 3rd generation thermostat, not the nest thermostat E. These are two different things.
The diagram you have posted is for the 3rd generation nest heat link, not for the thermostat E.

Following your advice to connect brown and blue to the thermostat E will cause a short circuit when it calls for heat.