Replace Trane TCONT900AC43UA Thermostat with CT100

Anyone have any experience with replacing a Trane TCONT900AC43UA thermostat which has only 3 wires with a C100. I bought two CT100’s not realizing one of my systems is newer and uses the TCONT900 3 wire. Am I SOL and need to find a different ZWave thermostat (instead of the Ct100?)

Any help will be appreciated.

The TCONT900 is a communicating thermostat so I’m pretty sure you can’t just replace it with a standard thermostat control like a CT100. You need to talk to an expert on your HVAC equipment.

I went through a great internal debate when I recently replaced my Nest controlled single-stage system with a 2 stage gas furnace/variable speed heat pump combination because one of the big trade offs was that the variable speed units only work proprietary thermostats. No guarantee that’s the case with your equipment but only somebody that understands the details of your equipment will know for sure.