Term used to describe our ability, as humans, to exist, without jeopardizing the ability of future generations to do the same.

An earth warming process caused by the atmosphere’s absorption of the heat energy radiated from the earth’s surface.

Meets the needs of the present without compromising the ability of the future generations to meet their own needs.

Companies looking to go “Green” incorporate sustainable design into their building and facilities.

urban air or surface temperatures that are higher than nearby areas.

energy that causes molecules to be in motion and to raise the temperature of a substance.

word used to describe the level of heat or molecular activity, expressed in Fahrenheit, Rankine, Celsius, or Kelvin units. Another word for it is heat intensity.

force per unit of area.

The weight of the atmosphere’s gases pressing down on the earth. We use the term when we refer to weather conditions.

a word used to describe the level of heat or molecular activity, expressed in Fahrenheit, Rankine, Celsius, or Kelvin units which are absolute temperatures. It is another word for temperature.

Use 0 as their lowest value and start where molecular motion starts. In other words, the temperature at which molecular motion stops.

The amount (quantity) of heat required to raise the temperature of 1lb of water 1degrees F. In other words, this term is used to describe the quantity of heat energy or heat content.

Heat transfer from one molecule to another within a substance or from one substance to another.

Heat transfer from one place to another one using a fluid.

The movement of fluid by mechanical means.

The natural movement of a gas or fluid caused by differences in temperature.

Heat that transfers or passes through air, heating solid objects that in turn heat the surrounding area.

Heat that causes a change in temperature.

heat required to convert a solid into a liquid or vapor, or a liquid into a vapor, without change of temperature.

the latent heat absorbed when refrigerant evaporates.

The latent heat given of when refrigerant condenses.

The amount of heat energy required to change the state of a substance from a liquid to a solid or from a solid to a liquid.

The amount of heat required to raise the temperature of 1lb of a substance to 1 degrees F.

Air at sea level at 70 degrees F when the atmosphere’s pressure is 14.696 psia.

A device used to measur4e atmospheric pressure that is commonly calibrated in inches or millimeters of mercury.

C-shaped tube manufactured of thin metal and closed on one end used in a gauge to indicate pressure. When pressure is increased inside, it tends to straighten.

the gauge that measures the low-side pressure in an air-conditioning or refrigeration system.

The gauge used to measure the pressure on the high-pressure side of an air conditioning or refrigeration system.

Is a substance that takes up space and has weight.

Substances that form when different elements combine chemically.

A state of matter characterized by particles arranged such that their shape and volume are relatively stable.

A substance where molecules push outward and downward and seek a uniform level. In other words, such as water or oil, that is neither a solid nor gas.

The vapor state of matter.

matter held together to the extent that it is considered one body.

the force that matter (solid, liquid, or gas) applies to a supporting surface when it is at rest.

the weight per unit of volume of a substance.

The volume occupied by 1lb of a fluid.

Gas law that states an inverse relationship between pressure and volume at a constant temperature.

Law that states that energy cannot be created nor destroyed but can be converted from one form to another.

A unit equal to 33,000 ft-lb of work per minute.

Is the amount of heat required to melt 1 ton of ice in a 24-hour period.

refers to the relationship of a liquid and vapor in a closed container. If the temperature increases, the pressure will also increase. If the temperature is lowered, the pressure will decrease.

A term used to describe a substance when it contains all of another substance it can hold.

the pressure at which a refrigerant will change state.

The pressure of the vapor in a vessel that pushes against the liquid or the pressure exerted on top of a saturated liquid.

A pump that pumps vapor (refrigerant or air) from one pressure

Term used to describe compressors that use large impellers to increase the kinetic energy and pressure of the refrigerant as opposed to compressors that use mechanical means for compression.

Is a heat transfer surface that rejects both sensible (measurable) and latent (hidden) heat from the refrigeration system.

The refrigerant line that connects the discharge port of the compressor to the inlet of the condenser.

Removing heat from the superheated hot refrigerant gas down to the condensing temperature.

a value or small fixed-size tubing or orifice that meters liquid refrigerant into the evaporator.

To remove moisture from the air.

The point where the saturated liquid and vapor lines meet at the top of the saturation curve.

is expressed in Btu/lb. and is the quantity of heat that each pound of refrigerant absorbs from the refrigerated space to produce useful cooling.