HVAC Related Definitions
Definitions of some commonly used terms in Heating, Air Conditioning, Ventilation and Refrigeration. We are continuously adding more definitions, so we welcome you to return to learn more definitions of commonly used HVAC terms.
Capillary Tubing: Tubing used in older refrigeration or air conditioning systems that is of very small diameter that expands condensed, high pressure, liquid refrigerant. Thereby controlling the flow of high-pressure liquid into the evaporator.
Condenser: The part of a refrigeration or air conditioning system that condenses refrigerant in its gaseous, vapor, state into a liquid form.
Enthalpy: Enthalpy is the quantity of heat necessary to raise the temperature of a substance from one point to a higher temperature. The quantity of heat includes both latent and sensible. It is a common term used in refrigeration.
Evaporator: The part of a refrigeration or air conditioning system that evaporates a refrigerant (taking the refrigerant from it's liquid state to a gaseous state) thereby absorbing heat.
Freon: Registered trade name for the chlorofluorocarbons (CFCs). It is the brand name of any of several non-flammable refrigerants based on halogenated hydrocarbon including R22, R12 and R134A.
Metering Device: A component of a refrigeration or air conditioning system that controls the flow of high-pressure liquid into the evaporator. Types of metering devices include capillary tubing, thermostatic expansion valves and automatic expansion valves.
Refrigerant: A liquid such as R22, R410A, R134A and R502 that is use in cooling devices to absorb heat from surrounding air and transfer it to another location, ie outside of a house or building.
Subcooling: A process in refrigeration in which refrigerant in its liquid state is at a temperature lower than the saturation temperature at a given pressure. Heat energy is being taken out of the subcooled refrigerant.
Superheating: A process in refrigeration in which refrigerant in a vapor state has a rise in temperature by having heat energy added to it.
Vacuum Pump: A device used in evacuating a refrigeration or air conditioning system. It takes a closed system to a point where any moisture can evaporate and be taken out of the system before refrigerant is introduced or reintroduced to the system. Helps ward off any contaminants before the system is charged with refrigerant.
Capillary Tubing: Tubing used in older refrigeration or air conditioning systems that is of very small diameter that expands condensed, high pressure, liquid refrigerant. Thereby controlling the flow of high-pressure liquid into the evaporator.
Condenser: The part of a refrigeration or air conditioning system that condenses refrigerant in its gaseous, vapor, state into a liquid form.
Enthalpy: Enthalpy is the quantity of heat necessary to raise the temperature of a substance from one point to a higher temperature. The quantity of heat includes both latent and sensible. It is a common term used in refrigeration.
Evaporator: The part of a refrigeration or air conditioning system that evaporates a refrigerant (taking the refrigerant from it's liquid state to a gaseous state) thereby absorbing heat.
Freon: Registered trade name for the chlorofluorocarbons (CFCs). It is the brand name of any of several non-flammable refrigerants based on halogenated hydrocarbon including R22, R12 and R134A.
Metering Device: A component of a refrigeration or air conditioning system that controls the flow of high-pressure liquid into the evaporator. Types of metering devices include capillary tubing, thermostatic expansion valves and automatic expansion valves.
Refrigerant: A liquid such as R22, R410A, R134A and R502 that is use in cooling devices to absorb heat from surrounding air and transfer it to another location, ie outside of a house or building.
Subcooling: A process in refrigeration in which refrigerant in its liquid state is at a temperature lower than the saturation temperature at a given pressure. Heat energy is being taken out of the subcooled refrigerant.
Superheating: A process in refrigeration in which refrigerant in a vapor state has a rise in temperature by having heat energy added to it.
Vacuum Pump: A device used in evacuating a refrigeration or air conditioning system. It takes a closed system to a point where any moisture can evaporate and be taken out of the system before refrigerant is introduced or reintroduced to the system. Helps ward off any contaminants before the system is charged with refrigerant.
