An Alphabetized List of Terms for the HVAC Technician
HVAC technicians are trained to work on heating and refrigeration systems in residential, commercial, and factory buildings. It is important that they understand some basic terms that are related to engineering and mechanics, as well as some of the more specific terms that are used within the industry.(1)
If you’re thinking about a career as an HVAC technician or are perhaps already pursing your Associates degree in HVAC technology, then the following guide may be able to help you become familiar with the common lingo of HVAC technicians and give you a “leg up” in your pursuit of a career.(2)
ACCA – Air Conditioning Contractors of America
ACH – Air Changes per Hour
AFUE – Annualized Fuel Utilization Efficiency
ARI – Air-Conditioning and Refrigeration Institute
Air Cleaner – a filtering device for removing impurities from air
Allergen – any substance, often a protein, that induces an allergy: common allergens include pollen, grasses, dust, and some medications.
BTU – British Thermal Unit
Carbon Monoxide – a colorless, odorless, poisonous gas, CO, that burns with a pale-blue flame, produced when carbon burns with insufficient air: used chiefly in organic synthesis, metallurgy, and in the preparation of metal carbonyls, as nickel carbonyl.
Celsius – Also, Centigrade, pertaining to or noting a temperature scale (Celsius scale) in which 0° represents the ice point and 100° the steam point. Symbol: C.
Chiller – a device for cooling or refrigerating.
Coil – an arrangement of pipes, coiled or in a series, as in a radiator.
CAV – Constant Air Volume
CAE – Combined Annual Efficiency
CFM – Cubic Feet per Minute
Dehumidifier – an appliance for removing moisture from the air, as for lowering the humidity in a storage room.
Diffuser- (in various machines or mechanical systems, as centrifugal pumps or compressors) a device for utilizing part of the kinetic energy of a fluid passing through a machine by gradually increasing the cross-sectional area of the channel or chamber through which it flows so as to decrease its speed and increase its pressure.
DOE – Department of Energy
Economizer – a device for warming feed water with gases entering the chimney or stack.
Enthalpy – a quantity associated with a thermodynamic system, expressed as the internal energy of a system plus the product of the pressure and volume of the system, having the property that during an isobaric process, the change in the quantity is equal to the heat transferred during the process. Symbol: H.
Evaporator- the part of a refrigeration system in which the refrigerant absorbs heat and changes from a liquid to a gas.
Energy Star® – A designation of the U.S. Environmental Protection Agency (EPA). Attached to HVAC products that meet or exceed federal guidelines for energy-efficient performance.
Fahrenheit – noting, pertaining to, or measured according to a temperature scale (Fahrenheit scale) in which 32° represents the ice point and 212° the steam point. Symbol: F.
Furnace – a structure or apparatus in which heat may be generated, as for heating houses, smelting ores, or producing steam.
Grille – an opening, usually covered by grillwork, for admitting air to cool the engine of an automobile or the like; radiator grille.
HSPF – Heating Seasonal Performance Factor
Heat Pump – a device that uses a compressible refrigerant to transfer heat from one body, as the ground, air, or water, to another body, as a building, with the process being reversible.
HEPA Filter – High Efficiency Particulate Absorbing filter
HSPF – Heating Seasonal Performance Factor
Humid – containing a high amount of water or water vapor; noticeably moist
Humidifier – a device for increasing the amount of water vapor in the air of a room or building, consisting of a container for water and a vaporizer.
HVAC – Heating, Ventilation and Air Conditioning.
Latent heat – heat absorbed or radiated during a change of phase at constant temperature and pressure.
MAU – Makeup Air Unit
MERV – Minimum Efficiency Reporting Value
Modulate – to regulate by or adjust to a certain measure or proportion; soften; tone down.
OAT – Outside Air Temperature
Plenum- a space, usually above a ceiling or below a floor, that can serve as a receiving chamber for air that has been heated or cooled to be distributed to inhabited areas.
PTAC – Package Terminal Air Conditioner
Radiation – the process in which energy is emitted as particles or waves.
Refrigerant – a cooling substance, as ice or solid carbon dioxide, used in a refrigerator.
SHR – Sensible heat ratio
Static Pressure – the pressure exerted by a fluid that is not moving or flowing.
Thermostat – a device, including a relay actuated by thermal conduction or convection, that functions to establish and maintain a desired temperature automatically or signals a change in temperature for manual adjustment.
UFAD – Underflow air distribution
(2) Employment is not guaranteed for students or graduates.