A complete, up-to-date, illustrated guide to the installation, maintenance, and service of gas, oil, and electric forced warm air heating and heat pump systems. Explores--in great detail--a large base of newer as well as traditional equipment, using the principles and practices of older furnaces as a means of understanding the newer, electronically controlled, high-efficiency furnaces. Features detailed discussion of the operation and diagnosis of controls--from the thermocouple to the SmartValve(R)--and provides a complete overview of all aspects of residential and light...