I found this thermostat after unsuccessfully trying another conventional digital programmable thermostat. It is the only one I know of that can be programmed to successfully control a steam radiator system. It has a setting just for that. It also learns the response of your heating system and can have the temperature reach the setpoint at the time of the set program; meaning that if you want the room to be at 68 degrees at 7:00 AM it will be there at 7:00, not start heating at 7:00, a nice touch. The temperature control is excellent, with no large temperature swings.Get more detail about 5-1-1 PROGRAM THERMOSTAT.