Compatible with Trane Heat Pump?

[Perryje]

I bought a Nest Learning Thermostat Gen3 I believe (10 connection points, blue bubble level).  This thermostat will be installed with my new-build Trane Heat Pump.  Trane wiring block is attached for reference.  NOTE: Look closely at the 2nd wire label under the wires on the right side.  Orange=O/B,  Black=E,  Red=R.  There are no alternate labels for wires on left side. 

After installation the nest thermostat has only the tiny red blinking LED above the Nest Logo.  Nothing is displayed of any sort.

Defective thermostat? 

Wiring issues? 

Ideas? 

Thanks, John 

https://photos.app.goo.gl/W6dvMnTEf3MgTVJf9

[Patrick_Caezza]

@Perryje 

You have a heat pump and the left-hand labels on the right terminal block are the correct ones to use.

Just match the labels and you'll be good to go.

The black wire is for emergency heat and gets connected to the * terminal on the Nest; you will configure it as such.

The white wire goes to W2/Aux and is configures as AUX heat

[Perryje]

After connecting the wires as recommended by the Nest app, and the Google expert, The display remained black/blank.  I later found out this was because the thermostat needed an hour or more to charge it's internal battery.  After allowing the thermostat to sit (while tiny red led blinks) the display came to life and allowed me to proceed with the setup. 

[Perryje]

Now the stage 2 cooling and fan come on for about 2 minutes then shuts off and stays off, but the display remains blue as if the thermostat 'thinks' it's cooling. I can further support with answers to your questions and pictures.

My system is a brand new Trane all-electric (single fuel) heat pump. My newly installed thermostat is a Nest 3rd Gen (10 wire block with blue bubble level). Cooling is the active mode. Target temp is set well below current ambient temp with the blue cooling screen indicating the thermostat "thinks" it's cooling. Since this is a brand new install, there is no schedule data yet. I have not yet activated the home/away feature. No error codes.

My concern is upon completing the initial install the base warned about possible incomplete wiring, but I may be misinterpreting, but please refer to the pictures. Pictures reflect the original wiring block from original technician install of OEM Trane thermostat. Then a picture of my conversation to the Nest wiring block. Then a picture of the setup screen that implies something is not complete ("check" terminals). I have not tried to confirm heating yet, as it is 86 indoors and I just can't muster the strength to heat the house... One thing at a time.

Is my wiring correct, since the setup screen says "check" these wires (see picture)?

Should the heat pump type be zero ("0") in the hardware description /setup?

 

 

 

 

[jenniffert]

Hi Perryje,

Thank you for reaching out to the community! I’m sorry to hear that your two-stage cooling system shuts down after two minutes. I'm happy to help with your wiring concerns.

@Patrick_Caezza, thanks for your help, that's a great resource for everyone!

Regarding your question @Perryje, about whether the wiring installation was correct, based on the pictures, the white wire should be connected to W2/Aux on the Nest Learning thermostat and is configured as AUX heat. In addition, I’d like to ask the following:

• Does the issue happen on cooling only, or both heating and cooling?
• Is this the first time you've activated cooling since the season changed? If so, was the old thermostat working correctly?
• When was the last maintenance and cleaning service performed on your HVAC system?

In the meantime, I’d suggest the following steps:

• Check the air filter. Your HVAC system requires good airflow to operate properly. A clogged air filter can restrict airflow over the cooling coils, causing them to freeze and shut down the system.
• Ensure the wires are fully inserted into the terminal and the connector buttons are securely pushed down. This guarantees proper wire connections. I also recommend cleaning the wires with a paper towel, as dust can sometimes prevent the base from recognizing the wires. You can check out this article for more information: Troubleshoot strange heating or cooling behavior. Important: Before touching any wires, turn off the power to your HVAC system at the breaker box.
• Then, check the power readings by going to Settings > Technical Info > Power on your Nest Learning thermostat and provide me with the VOC, VIN, and IIN values.

Please keep me posted.

Best regards,

Jenniffer