Converting Trane XL1200 A/C to heat pump

[oxfletch]

Is it possible to use an existing Trane XL1200 unit that's working great for A/C as a heat pump as well?

It seems from a basic Google search like the unit is capable of being a heatpump ... what would be involved in making it run that way? Just changing wiring to thermostat, or much more complicated?