Glossary of HVAC Terms
Glossary of HVAC Terms
The heating, ventilation, and air conditioning (HVAC) industry has its own language, which can be confusing to those who don't work in the field. This glossary provides explanations of the most common HVAC terms.
Air Conditioning
The cooling of air to a comfortable temperature for humans to live in. Air conditioning can be done with a system that uses refrigerants to cool the air or a system that uses vapor compression.
Airflow
The rate of air movement, usually expressed in feet per minute (FPM).
Air Handler
A device used to distribute conditioned air throughout a building. Air handlers are typically placed in the attic or on the roof of a building.
Btu
British thermal unit. A unit of measurement for the amount of heat energy required to raise the temperature of one pound of water one degree Fahrenheit. (1 Btu = 0.293 watt-hour)
Cooling
The lowering of air temperature to a comfortable level. Air cooling can be done with a system that uses refrigerants to cool the air or a system that uses vapor compression.
Ductwork
The network of pipes that distributes conditioned air throughout a building. Ductwork can be made of metal, fiberglass, or plastic.
Evaporator Coil
The part of a refrigeration system that removes heat from the refrigerant, which causes it to evaporate and expand. The refrigerant then moves through the compressor, which compresses it, and then the refrigerant goes through the condenser coil, which removes the heat from the refrigerant, causing it to condense back into a liquid. The refrigerant then moves through the expansion device and back to the evaporator coil, where the process starts over.
Flex Duct
A type of air duct made of flexible material, such as plastic. Flex duct can be used to connect air conditioning equipment to the air distribution system.
Furnace
A device that heats air to a comfortable temperature for humans to live in. Furnaces are typically placed in the basement or on the roof of a building.
Heat Pump
A device that transfers heat from a cooler area to a warmer area. Heat pumps are typically placed in the basement or on the roof of a building.
Indoor Air Quality
The quality of air in a building. Indoor air quality is often affected by the quality of air outside the building. Factors that can affect indoor air quality include humidity, temperature, particulates, and carbon dioxide levels.
