Extra-large, touchscreen display shows room temperature, set temperature and current time all at once. Effortless menu-driven programming guides the user through programming process, only showing necessary information and choices - eliminates unnecessary clutter. Separate programming for each day of the week - 4 periods per day. Universal application - works with conventional and heat pump systems up to 2H/2C; it's one thermostat for nearly every application. Large, backlit display shows room temperature, set temperature and current time all at once. Maximum comfort - Smart Response® technology learns the amount of time a system needs to reach a desired temperature and adjusts accordingly. Program is retained in memory in the event of a power outage. Real-time clock automatically adjusts for daylight savings time. Precise temperature control of +/-1 degree Fahrenheit for consistent comfort. Includes change reminders for filters and low batteries. Armchair programming allows user to program the thermostat from his or her sofa or chair. 24 - Volt Heating and Air Conditioning Systems: Compatibility Single Stage Heating and Cooling Yes Multistage Heating and Cooling Yes Heating Only Yes Cooling Only Yes Furnace (Warm Air) Yes Central Air Conditioning Yes Heat pump without Auxiliary Heat Yes Heat pump with Auxiliary Heat Yes Hot Water Yes Steam or Gravity Yes 750 Millivolt Yes Gas Fireplaces Yes Electric Baseboard Heat No