The Vent-Miser lets you program your vent to automatically open and close, controlling airflow in unoccupied rooms to save you money. Shut down the heating or cooling in spare guest rooms, bedrooms during the day, kitchens, dining room and office at bed time to prevent wasted energy. Running independently of your heating and cooling system, the Vent-Miser features a convenient digital module that can be removed for programming and for installing or replacing the battery.