The Heil® True Dual Fuel programmable thermostat works by using the most economical fuel for heating - gas or electricity - depending on outdoor conditions. It monitors outdoor temperatures and signals the system to switch automatically to the most economical energy source. It protects the equipment by keeping the heat pump and furnace from running at the same time and maintains efficiency by ensuring that the heat pump fully defrosts. Features include seven-day programming, three-stage heating and two-stage cooling, digital dealer contract information display, blue backlit display, and humidity control.
International Comfort Products, P.O. Box 128, Lewisburg, TN 37091; 931-270-4222; 931-270-4166 (fax); www.goheil.com