Replacing Honeywell CM921 with Nest 3rd Gen Logic Combi

[Msultan]

I am trying to install google nest and replace Honeywell thermostat for my Logic Combi 30 boiler. I have seen many forums but bit confused about the wiring. Help will be much appreciated.

Currently, I have 4 cables in my thermostat base unit. N, L, A, and B. Please can you advise which one will connect to which on nest thermostat.

Many thanks for your help in advance.

 

[ianmcd]

N to N
L to L
A to 2
B to 3

 

[Msultan]

Thanks Ian. Is Ideal Combi 30 Boiler compatible with Nest? Will I be able to control water temperature as well from Nest or just Heating?

Many thanks

 

[muggles]

Thanks Ian. Is Ideal Combi 30 Boiler compatible with Nest? Will I be able to control water temperature as well from Nest or just Heating?

Many thanks

It can control hot water temperature if it's connected using the OpenTherm connections, but you can't connect those yourself as it needs wiring altering inside the boiler, which is Gas Safe engineer territory

 

[Msultan]

Thanks so much for your prompt responses. Much appreciated. I will connect it today and if any issues, I will report back.