A simple, easy to use 5-2 day programmable thermostat. A programmable thermostat can save you up to 33-Percent off your energy bill, if used as directed. You set it up to adjust the temperature when you are away or asleep-times when you don"t necessarily need to heat or cool your home to optimum comfort-and your HVAC equipment runs less. Plus, your heating or cooling comes back to the comfort level you desire before you come home or wake up. Honeywell programmable thermostats are easy to install and are pre-programmed for your convenience. For more than a century, Honeywell thermostats have been the popular choice of homeowners. This thermostat is compatible with single-stage heating/cooling systems, heating, cooling, heat pumps without backup heat, mill volt, pellet stoves and fireplaces. It does NOT work with electric baseboard heat (120-240 V), heat pump systems with backup heat or multi-stage heating/cooling.