Nest compatibility

[Lazri]

Which Nest would work with this wiring? There is also like a metal jumper/plate connecting R and RC.
Deciding on which one to buy: Regular Nest or Learning Nest?
Thank you

[HVAC]

Any nest would work it’s up to you what you prefer. Need to verify where does that blue wire connected to B cause you have a brown wire connected to O which tells me you have a heat pump system & you can’t have both O & B wires connected to nest it’s 1 or the other. Verify what’s connected on the control board to see what you need to connect maybe the blue wire is connected to C so you can put it in C on nest. You don’t need the metal jumper on the nest you need to put the red wire to R or RC / RH depending on which module you get. Good luck. 

[Lazri]

 

Thank you! This is the panel. I do not see a brown wire connected anywhere. At some point there was a humidifier connected to the system, which I do not use. Maybe the brown wire was for that one. 
any thoughts please?

[HVAC]

It’s possible brown was to humidifier. Looks like You have 2 zone system & it’s set up as a gas heating. It’s the blue wire that I was wondering about also that connected to B on your old stat. The right side of that zoning board is where 2 of your thermostat connect to I don’t k ow which zone that old stat base pic you posted is connected to. I see bottom slots has a blue wire connected to possibly Y & has a short yellow wire on G  jumped between Y & G. Pic is kind of top angle & fuzzy can’t see it that clearly. You should have a separate transformer powering up that zoning board & you need to choose a wire that’s not connected & connect it to C on nest & at zone board to get 24 volts to nest all the time. Hope that helps. Good luck  

[Lazri]

Thank you for your help. Last question: when you say select a wire that’s not connected, do you mean one not connected to zone 1 thermostat (upper right hand on the picture)? 

[HVAC]

Not sure which upper right hand honestly there’s so many wires. 
the set with only 2 wires connected goes to your damper so not those. You have 2 sets of wires going to 2 stats that you have inside and they’re connected to where it says thermostat in dark blue see if you might have extra that are wrapped up & not in use & use one of them to connect to C slot in zoning board and at nest stat C slot. Good luck. 

[Lazri]

Perfect. Thank you. 

[EdmondB · Accepted solution]

Hello Lazri, 

Checking in — do you still need help with the wiring configuration on your Nest thermostat? Let me know if you need more help.

Thanks for the help, @HVAC.

Best,
Edmond