I have a Intertherm gas furnace with air conditioning. I would like to replace the intertherm thermostat with a programmable one. What one would be compatible with this system?

Thank You

Usually the compatibality is listed right on the new thermostat box. You need a one stage heat and a one stage cool thermostat. Is this in a mobile home? If it is you will have to see how many wires you have going to the old thermostat. If your unit has a rocker switch that says heat off cool most of the programmable t stats will not work because it is a two wire system