The Simple thermostat is designed for conventional central heating (furnace or boiler), cooling (AC), and heat pumps. It does not support line voltage or millivolt systems. Power from a common wire, also known as a C-wire, is required.
If you know you have a C-wire, check your wiring compatibility now. Otherwise, follow the steps below to determine if an existing C-wire is available.
Do you have an electronic thermostat with a display and Up/Down buttons?