The distribution or movement of air.

The indoor part of an air conditioner or heat pump that moves cooled or heated air throughout the ductwork of your home. An air handler is usually a furnace or a blower coil.

Microscopic living organisms suspended in the air that grow and multiply in warm, humid places.

A British thermal unit is a unit of heat energy. One Btu is the amount of heat required to raise one pound of water by one degree Fahrenheit. The higher the Btu rating, the greater the heating capacity of the system.

An odorless, colorless, tasteless, poisonous and flammable gas that is produced when carbon burns with insufficient air.

System in which air is treated at a central location and distributed to and from rooms by one or more fans and a series of ducts.

Stands for Cubic Feet per Minute. This measurement indicates how many cubic feet of air pass by a stationary point in one minute. The higher the number, the more air is being moved through the ductwork by the system.

The part of the outdoor air conditioner or heat pump that compresses and pumps refrigerant to meet household cooling requirements.

The outdoor portion of an air conditioner or heat pump that either releases or collects heat, depending on the time of the year.

A movable plate, located in the ductwork, that regulates airflow. Dampers are used to direct air to the areas that need it most. Typically used in a zoning application.