HVAC motors power HVAC equipment to provide heating, cooling, and air circulation in indoor environments. They are commonly used in air coolers, roof ventilators, air circulators, and condensing units. Belt-drive motors drive a belt or pulley to power equipment and allow for adjustable operating speeds. Direct-drive motors include condenser fan motors, pedestal fan motors, room air conditioner motors, and unit heater motors. They mount directly to the drive shaft of HVAC equipment, which minimizes friction during operation and increases efficiency. Direct-drive motors produce less noise and vibration than belt-drive motors. C-frame motors are suitable for use in small fans, such as in range hoods and electric heaters. Draft booster motors and oil burner motors power fans and pumps in gas furnaces and oil burners. OEM replacement motors, 3.3" diameter motors, and 4.4" diameter motors are typically used to replace damaged motors with the same specifications in compatible equipment.