The Lyric thermostat is designed to work on most low voltage heating and cooling systems, at 24 Volts. Gas and oil furnaces, heat pumps, and hot water systems are examples of these low voltage systems. The thermostat can also support multi stage systems with more than one stage of heating and cooling. The Lyric thermostat does not work for 110V or higher line voltage systems, such as electric baseboard heaters. Thick black, red or white wires connected with wire nuts running to your existing thermostat will typically mean you have a high voltage system. If your system is high voltage, we will help you find another compatible thermostat. To identify your home heating and cooling system type, click here. If your system is high voltage, we will help you find another compatible thermostat.