Question about Nest Learning Therm. compatiblity with a hybrid AC system

[tronboy]

I think I know the answer to this, but I'm seeking the wisdom of the forum to either confirm or disagree with my thinking.

I have a "hybrid" residential system in that the heater/blower unit is multistage (2 stage) with a variable speed blower but the outside condenser unit is single stage.   The thermostat hookup is an old 5-wire connection, but the thermostat was left in a multi-stage (MS2) setting by the installers.  There is only one system on the house (not a heat pump), and the system is not zoned.

I'm figuring this system is being controlled like a single stage unit by the thermostat, and the extra control signals that may be activated by the thermostat are doing nothing since they are not connected.  I'm also figuring (from the manual) that the heater/blower unit is simply using a time delay to control the fan speed (the blower fan does change speeds).  If all of this adds up, then a Nest thermostat wired for single stage operation should be compatible with the system.  Does this sound right or have I missed something.

Admittedly, one thing I could try would be to reconfigure the thermostat to single stage operation and verify that the system operates the same.  Is there any other wisdom out there for such a system as I've described and Nest compatibility?

[Markjosephp]

Hi tronboy,

Thank you for taking the time to let us know about your inquiry. I'd be happy to take a look at this for you.

To check your system's compatibility with the Nest Thermostats, could you share with us a photo of your thermostat's wiring? Also, the make and model of your system.

I'll look forward to your response.

Regards,
Mark

[tronboy]

Thank you very much for your reply.  I managed to answer my own question with a little more research in the manual.

Thanks again, and I appreciate the help.

[Markjosephp]

Hello tronboy,

Sounds great! I appreciate you posting and updating us on your efforts to address your concern and find a fix. I wanted to ensure that everything was covered here.

Please let us know if you have any further questions; otherwise, we'll close the thread in 24 hours.

Regards,

Mark