Which nest should I purchase.

[Bny1946]

Can anyone tell me which nest is compatible with a 4 wire heat pump? The schematic shows yellow, blue, red, and brown wire going to the thermostat. 

[Patrick_Caezza]

@Bny1946 

Can you post a picture of your current thermostat's wiring here?

Any of the Google Nest thermostats can be used with a basic heat-pump system. It will just depend on what features you want.

[Bny1946]

• @Patrick_CaezzaI’m sorry. It’s at my son’s house, can’t get one very soon. I have a picture of the pump wiring, but can’t post it. It has yellow, blue red and brown on the pump side, going to white green red and yellow. I’m concerned about needing a c wire.
  

[Patrick_Caezza]

@Bny1946 

I always recommend that a C wire be installed. If there isn't a spare wire that can be used, then the Google Nest Power Connector is the recommended solution.

To post a picture or image try this,

[Bny1946]

@Patrick_Caezza I don’t have that option in my reply window, sorry. I don’t think I’m going to have access for the c wire

[Patrick_Caezza]

@Bny1946 

The Learning thermostat can function without a C-wire just fine 90% of the time.

It can take a few posts before that icon shows up, so no worries

[Bny1946]

Thanks for your help