Glossary of Applied Air HVAC Terminology

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Radiation
The transfer of heat directly from one surface to another. (No intermediate air acting as a transfer mechanism required).
Refrigerant
Substance used in refrigerating mechanism. It absorbs heat in evaporator by change of state from a liquid to a gas, and releases its heat in a condenser as the substance returns from the gaseous state back to a liquid state.
RH
Relative Humidity
Rotor
The rotating part of the motor which includes the propeller assembly.
RPM
Revolutions per minute, the measurement of fan blade speed.