Nest Learning Thermostat with Lennox 2-stage HVAC system

[Dawntreader1]

I just had a new Lennox 2-stage heat pump system installed, and connected to my Nest thermostat.

I've had the thermostat for a few years, working with my old 1-stage system.  When the technicians installed the new system, I guess due to the way they wired it, my Nest recognized it as having two stages, the only problem is that it's only running in Stage 2, at least according to the thermostat and app where it always says "Stage 2 Cooling".  It's like it doesn't know how to modulate between the two stages, so it just runs full blast until it reached the set temp, and then shuts off.  

Is there something that needs to be reconfigured in the thermostat settings to help it communicate with the new system better?  According to the Nest manual, the wiring is correct for a 2-stage heat pump system.  

I was on the phone with Google support for about 2 hours today, and didn't really get anywhere, so if anyone has any pointers, I'd really appreciate it. 

Here's the stats of my HVAC system:

MFR: LENNOX TYPE: 2-STAGE
CONFIG: HORIZ FUEL: SPLIT HP

SERIES: XP21 SIZE: 5.0
OUTDOOR UNIT: XP21-060
INDOOR UNIT: CBA38MV-060 

Here's my current thermostat wiring:

[HVAC]

Try pulling out the brown Y2 wire don’t let it touch anything tape it off or cut and strip later. Put your nest back re configure to 1 heat pump zone and see if thats still works at full blast. If so then you won’t have 2nd stage otherwise need on hand tech to verify correct set up. Good luck 

[Jenelyn_O]

Hi there,

Thanks for posting in the Google Nest Community forum. Could you please share your case ID? 

I appreciate the input, @HVAC.

Best,

Jenelyn

[Dawntreader1]

I'm not sure what you're referring to by case ID?

[Jenelyn_O]

Hi Dawntreader1,

I'm sorry for the confusion. You mentioned that you were on the phone with Google Support. Could you please check your inbox if you received a case ID from them? It will help us to take a closer look at your case. 

Thanks,

Jenelyn

[Dawntreader1]

My case number was 4-1998000034945

[Markjosephp]

Hello everyone,

I appreciate your assistance here, Jenelyn.

Thanks for sharing your support ID number, @Dawntreader1. Do you still have a photo of your old thermostat wiring set up? If so, please share it with us so we can determine how it was labeled. In addition to what was shared by HVAC, the Time-to-Temperature algorithms of the Nest Thermostats are used to calculate how long it will take to heat or cool your house to a particular temperature. This estimate helps your thermostat determine when to activate various heating or cooling phases if your system has more than one to attain the desired temperature quickly and effectively.

Your thermostat will activate extra stages of cooling if the first stage of your system's cooling does not achieve your chosen temperature within a reasonable amount of time. If the goal temperature is raised by at least 5 to 10 degrees beyond the actual temperature, this typically occurs.

Let us know if you have more questions.

Best regards,

Mark