The combination of an electric heat pump and a forced air furnace is called a dual fuel or a hybrid system. Exchanging a central air conditioner for a heat pump significantly increases the startup investment but also provides considerable cost-saving benefits. During the summer months, the heat pump operates very much like a conventional air conditioner. It uses ductwork connected to vents to pull heat out of the air and create a cooling effect. Heat pumps are actually more effective at dehumidifying than an air conditioner, allowing for higher temperature settings and better energy efficiency. The heat pump truly excels when the cooler weather sets in. The flow of refrigerant literally reverses. The system takes advantage of ambient heat found in the outdoor air and delivers it into the house. The operation requires no burning of fossil fuels. By eliminating the combustion process, the heat pump avoids the generation of greenhouse gasses. There is no worry over carbon monoxide or fumes. This makes the system wonderfully environmentally friendly. Heat pumps are much cheaper to run than gas furnaces. They can be up to three times more efficient, using far less energy to produce the same amount of heat. For the majority of the year, the heat pump carries the workload of temperature control and provides ideal comfort. In areas with severe winter conditions, the heat pump will begin to struggle when the temperature drops below freezing. At that point, the furnace automatically starts up, takes over the workload and runs for as long as necessary. Having a dual fuel system ensures that the home is always comfortable and also takes advantage of the most advantageous source of heating at any given time.