Just to spruce up the temperature control a bit more, I replaced the original analog thermostat with a residential Honeywell digital unit. It was basically plug and play once you get the wiring right - the whole project tool all of about 30 minutes. Note there are thin wires connected to sometimes different color thick wires. The thin wires are off the original thermostat and are the wires that you screw into the new thermostat.
The original Coleman Mach compared to the New digital on the right. The digital uses two AA batteries as the power source.
After removing the Coleman, these are the original six wires. The new digital does not have a hi/lo fan speed setting, so I did not use all the wires - only four, and capped off the gray and blue. The thin wires are the correct ones to use for the color coding
Here the wires are in place, and the rest tucked back into the wall. Red is the original 12V, yellow is the A/C, white is the furnace, and green is the high fan speed.
The finished install - works perfectly, keeps the temperature way better, and best of all, I need not futz around with those tiny micro control switches any more!
