United CoolAir Glossary
The weight of water vapor per unit; grams per cubic foot or grams per cubic meter.
Gauge pressure plus atmospheric pressure (14.7 psi).
Fahrenheit temperature plus 460Âº. Absolute zero is minus 460Âº F. Theoretically at or below this point there is no heat energy at all.
Temperature at which all molecular motion ceases (-460Â°F and -273Â°C).
The ability to soak up another substance.
A solution or surface that is capable of soaking up (taking in) another substance or energy form.
The process of a material in extracting one or more substances as a gas or liquid accompanied by a physical change a chemical change or both.
A chiller that uses a brine solution and water to provide refrigeration without the aid of a compressor.
Refrigerator that creates low temperatures by using the cooling effect formed when a refrigerant is absorbed by chemical substance.
Air Conditioning Contractors of America
A storage tank placed in a suction line for separating any liquid entrained in the suction gas.
Acid condition in system
Condition in which refrigerant or oil in system is mixed with acidic fluids.
Tubing used in air conditioning and refrigeration. Ends are sealed to keep tubing clean and dry.
A chemical that is a form of aluminum oxide. It is used as a drier or desiccant.
Specially processed carbon used as a filter-drier; commonly used to clean air.
That portion of a regulating valve that converts mechanical fluid, thermal energy or electrical energy into mechanical motion to open or close valve seats.
Add-on heat pump
A heat pump system used in conjunction with a fossil fuel furnace. Sometimes referred to as a dual fuel system.
Compressing refrigerant gas without removing or adding heat.
Substance with the property to hold molecule of fluids without causing a chemical or physical change.
The adhesion of a thin layer of molecules of a gas or liquid to a solid object.
Act of combining a substance with air.
Device used to cause motion in confined fluid.
An invisible, odorless, and tasteless mixture of gases that surrounds the earth.
Process of adjusting the flow of air in duct systems.
The amount of air required to completely replace the air in a room or building; not to be considered air flow rate being delivered to the space.
Device used for removal of air born impurities.
Device used to control temperature, humidity, cleanliness, and movement of air in conditioned space.
A process whereby the temperature, the moisture content or humidity, the quality, and the movement of air within a space are controlled. The term quality means both cleanliness and freshness of air.
Air distribution outlet or grille designed to direct airflow into desired patterns.
The space between magnetic poles or between rotating and stationary assemblies in a motor or generator.
Fan-blower, heat transfer coil, filter, and housing parts of a system. (Typically meant as the evaporator section)
Valve used to remove air from the highest point of a coil or piping assembly.
Heat of compression is transferred from condensing coils to surrounding air. This may be done either by convection or by a fan or blower.
Air-to-air heat pump
A heat pump that uses outdoor air as the source of heat and transfers it to air inside the space.
Water and alcohol solution that remains a liquid below 32Â°F (0Â°).
The height at a point above a reference level, sea level or the earth's surface.
Temperature of a fluid (usually air) that surrounds an object.
Chemical combination of nitrogen and hydrogen (NH3). Ammonia refrigerant is identified as R-717.
Instrument for measuring the rate of airflow (using velocity).
Cooling a metal slowly from a high temperature to make the metal soft.
Annual Fuel Utilization Efficiency (AFUE) rating
A rating system for furnaces that compares energy input and energy output.
A device used with a start-stop control to reduce the control differential.
Air-Conditioning and Refrigeration Institute.
Formerly, abbreviation for American Standards Association. Now known as American National Standards Institute (ANSI).
American Society of Heating, Refrigeration and Air Conditioning.
Ratio of length to width of a rectangular air grille or duct.
Device that draws a sample of air through it to measure the humidity.
Movement produced by suction.
Standards issued by the American Society for Testing and Materials.
Atmospheric dust spot efficiency
Measurement of a device's ability to remove atmospheric air from test air.
Pressure that gases in air exert upon the earth (14.695 psi or 29.92 in. Hg).
To reduce to a fine spray.
Transformer in which both primary and secondary coils have turns in common. Step-up or step-down of voltage is accomplished by taps on common winding.
A liquid mixture having constant maximum and minimum boiling points. Refrigerants comprising the azeotropic mixture do not combine chemically, yet the mixture provides constant characteristics.