What is the definition of a package furnace unit? A package furnace unit is a type of home heating system that combines the components of a furnace unit into one convenient, self-contained unit. This type of unit is designed to provide efficient, space-saving heating. The package furnace unit typically consists of a furnace and a heat exchanger, both of which are connected to an air handling system. The furnace is responsible for creating heat, while the heat exchanger transfers the heat from the furnace to the air handling system and the air in the home. This type of unit is typically installed outside the home, and the components are connected directly to the ductwork for distribution throughout the home. Package furnace units are available in a variety of sizes and outputs, making them ideal for a range of homes. They are also often more energy-efficient and cost-effective than traditional heating systems. Package furnace units can also be more reliable and require less maintenance than other types of heating systems.