SunStar Liquid Propane Infrared Heater (Thermostat Temperature Control) SC18T1-LP Mid-Size Infrared Features:. Thermostat Control Operation. Ideal for areas up to 700 Square Feet. The 99% heating efficient designs require no outside venting&#44; so all the heat stays in the room. A dual purpose safety pilot system protects against oxygen depletion and any interruption in the