You may have wondered what the are differences and more importantly, which one do you need? When it comes time to replace your thermostat , say with a smart programmable thermostat with energy saving features, you need to know whether to replace it with a line voltage thermostat or a low voltage thermostat.
Line Voltage thermostats are commonly found with electric heating such as with baseboard heaters, electric wall heaters and electric heaters. They use direct current, 120 or 240 volts instead of the usual 24V found in newer homes.
Low Voltage thermostats are the most prevalent thermostats for residential use. 24 Volts is most common voltage type available. If you have gas heating or forced air heating, you likely have a low voltage thermostat.