ENERGY STAR CERTIFIED. See your energy use in the Monthly Energy Report, and help save even more with a schedule that adapts to your lifestyle, and by connecting with your utility efficiency program AUTO HOME AND AWAY MODE. Adjust your thermostat from anywhere with your mobile device, or let your home automatically react to your schedule with geofencing MULTI-ROOM FOCUS. Add Smart Room Sensors to focus the temperature on multiple rooms for comfort where it matters to you. (Sensors sold separately). Wire Configuration - 4-Wire. Supports Wi-Fi 802.11 B/G/N 2.4 and 5 GHz COMPATIBLE WITH: Forced air (gas, oil or electric), hot water and steam, and heat pumps with electric backup. Does NOT work with electric baseboard heat (120-240V). C-Wire Required. SMARTER, SIMPLER SETUP. Everything you need comes in the box, including a power adapter so that the T9 works in most homes. The T9 intuitively identifies your home’s heating and cooling type, making it easy to do it yourself Before purchasing, check to see if this thermostat is compatible with your home and to determine if your home needs a C-wire power adapter. Works with most heat/cool oil furnace systems. Will not work with heating only oil furnace systems unless a C-Wire is present.