Glossary

British thermal unit. The standard of measurement used to guage the amount of heat required to raise the temperature of one pound of water by one degree (Fahrenheit).

American Society of Heating, Refrigeration and Air Conditioning Engineer

Air Conditioning & Refrigeration Institute.

British thermal units per hour. 12,000 BTUh equals one ton of cooling.

The amount of air the system circulates through your home, indicated in cubic feet per minute (cfm). Correct airflow depends on the indoor unit, the ductwork, the outdoor unit, and even whether the filters are clean.

A system for controlling the humidity, ventilation, and temperature in a building or vehicle.

A piece of machinery that removes unwanted particles from moving air.

The portion of the central air conditioning or heat pump system that moves cooled or heated air throughout a home’s ductwork. In some systems a furnace will handle this function.

Annual Fuel Utilization Efficiency. A measure of a gas furnace’s efficiency in converting fuel to energy. The higher the rating, the more efficient the unit. The unit is more efficient when the rating is higher.

Abbreviation for American Gas Association, Inc.