Replace my rite temp thermostat with Nest Learning thermostat

[Trong]

Hi everyone,

I just got Nest Learning thermostat and I want to replace my old rite temp thermostat.

I have 2-zone HVAC for both heating and cooling

In the first zone, My old rite temp has 6 wire connections [red (Y), white (W), red (RH), green (G), green(B) and white (O)], but no C wire. On top of that, I have 2 separate O and B wire connections.

On the second zone, it is Honeywell rotary thermostat.

That troubles me to figure out how to connect properly, specially on O and B connection, in my first zone.

Can someone help?

I really appreciate for your time and effort.

Thank you.

[Jeff]

Hi everyone,

In an effort to keep content fresh on the forums here and prioritize current issues, I'm going to go ahead and close up this thread. If you have any outstanding issues from this post or any other problems, please feel free to open up a new discussion.

Thanks,
Jeff