Do you just want to set it for a temp, or is it programmable?
Ok, get a hair dryer,
set unit for heat and turn it up just 1 or 2 degrees above room temp. Let furnace kick on, and then start warming the area ariund the thermostat with the hair dryer. The furnace should shut off quickly. Then before the stat can cool...turn the system to cool and dial it to 1 degree below the room temp. The ac should kick on, the stat cool one degree and then kick off. Try that as a little project when you have the time. I wish you luck.