Refrigeration Principles Flashcards
British thermal unit
A unit for measuring heat quantity equal approximately to the amount of heat produced by the burning of ordinary kitchen match. More specifically, it is the amount of heat required to raise the temperature of one pound of water one degree Fahrenheit. (12000-btu in 1 ton)
Ambient air
The air surrounding any object
Capillary tube
A small diameter tube ( metering device ), whose bore and length are designed to permit the passage of a specific amount of liquid refrigerant or other liquid at a specific pressure drop.
Refrigerant charge
The amount of refrigerant in a system; to put in the refrigerant charge.
Coil
A heating or cooling element made of pipe or tubing with or without extensions or fins
Cooling coil
A term commonly used meaning the evaporator
Compression
In a compression refrigeration system a process by which the pressure of the refrigerant is increased
Compressor
A device for increasing the pressure I hear laden refrigerant vapors thus increasing the heat level ( super-heating) within those vapors so that the heat contained can be released into the outside atmosphere.
Condensation
The process whereby a vapor is changed to a liquid by removal of heat after it’s dew point (condensation temp) is reached.
Condenser
A vessel or arrangement of pipes or tubing, in which vapor is liquified by removal of heat.
Condensing unit
A refrigeration machine consisting of one or more power driven compressors, condenser, liquid receivers and other components
Conduction
The process of transferring heat along the elements of a substance as from a tube to a fin.
Convection
The transfer of heat by the movement of fluid or air
Refrigeration (mechanical) cycle
Complete cycle of refrigerant from a condensing unit (compressor-condenser) through a system of lines or tubing to the evaporator coil and back into the condensing unit; a cycle in which heat is absorbed in the evaporator and given up in the condenser
Dehydrate
To remove water in all forms from other matter
Dew point
The temp at which water vapor turns into liquid
Drier
A device placed in refrigeration system to attract and destroy unwanted moisture which may be in a system.
Evaporator
That part ( heat exchanger ) of a cooling system in which refrigeration is vaporized
Expansion valve
A thermostatically controlled valve, or metering device for controlling the boiling point and flow or refrigerant to the cooling element ( evaporator ).
High side
That part of the refrigeration system where refrigerant is under the greatest amount of pressure where heat is rejected (condenser section) . This is area of highest temperatures and highest pressures.
Liquid line
The tube or piping carrying liquid refrigerant from the condenser or receiver of a refrigeration system to a pressure reducing device.
Low side
Those parts of the refrigeration system where heat is absorbed at evaporator pressure; the cooling coil or evaporator with associated components; also commonly referred to as the suction side; this is the area of the lowest temperature And lowest pressures
