The procedures for estimation of the noise generated by home heating and air-conditioning systems will be discussed. The discussion on heating systems will include forced hot-air and water systems. To be included in the air-conditioning systems discussion are window units and central air-conditioning systems. The primary noise generators for heating systems include the furnace, burner, blowers, and unit heaters. The primary sources of noise in air-conditioning systems are the compressor, condenser (evaporative, cooling tower, or air-cooled), and blowers. Other sources of noise within such systems include the piping, circulators, ductwork, registers, and diffusers. Noise-control techniques will include location of the equipment, dissipative silencers, enclosures, lining of the ductwork, sizing of the ductwork, and vibration isolation. In addition, problems associated with the location of diffusers and registers, such as crosstalk between rooms, will be presented as well as methods for eliminating these problems.