As of 2015, a list of Trane air conditioner models is posted on the official Trane website, Trane.com. From the Trane homepage, click on the Products tab, then click on the Heating and Cooling link. The model numbers are listed under the Air Conditioners link.
To see a list of the Trane model numbers separated by series, click on the series name, and then click on the Product Specifications link. Scroll to the bottom of the Product Specifications page to see a comparison chart with the Trane model number, cooling capacity, nominal tons, height, width and depth for each machine.