GoControl GC-TBZ48 Two-Stage Heat Pump Wiring Question

I am attempting to replace my Trane TCONT803AS32DA (3 Heat/2 Cool) thermostat with the GoControl GC-TBZ48.

I thought for sure I could handle switching 6 wires out, but I am utterly confused between the two units with what goes where. I am suspicious that my home was wired with non-standard color codes, and I’m just not able to confidently identify the correct path.

I am hoping that there is somebody out there who can take a look at my photos and point me in the right direction.

I am 99% sure that I don’t have a C-wire, and that is OK because the GoControl can use batteries instead.

Thanks in advance.


Components:

  • Original Thermostat: Trane TCONT803AS32DA (3 Heat/2 Cool)
  • Replacement Thermostat: GoControl GC-TBZ48
  • Indoor Unit: Trane XV95
  • Outdoor Unit: Trane XL16i

Original Thermostat Wiring:

Indoor Unit Circuit Board Wiring:

(Since it’s hard to see with the black pipe in the way)


GoControl Instructions:


I guess my confusion lies in whether or not I should be referencing the “inner” or “outer” markings on the original thermostat to identify the wires.

Since I have a Heat Pump, I feel like I should be referencing the “outer”… and actually, they’re identical other than the “white” wire.

If I use “inner” it’s W1 and if I use “outer” it’s O.

But on the GoControl unit, the O terminal says “O or B”.

“Connect to the O terminal. Heat pump setup must set changeover valve to correct O or B setting”

“The changeover (or reversing) valve is used to change from heating to cooling operation. The HVAC system is either a Changeover with Cooling type (O) or Changeover with Heating type (B). Most are changeover with cooling, which is the default setting.”

It is unclear what is correct because when I look at the manual for the Trane XL16i, the only mention of “changeover” is:

“Cooling only and heat/cooling (manual and automatic changeover)”.
(https://www.bayareaservice.com/wp-content/uploads/2011/11/Download-Trane-XL16i-Product-Data.pdf) page 19

SO, my best guess is this:

However, I’m nervous that I don’t exactly understand what is going on, so before I actually fire this up and possibly blow up my house (haha not really worried about that), or do any damage at all, I thought I’d make this post and see if anybody has any advice to reassure me that I’m making the right choice.

I appreciate it!