RAC 40 Quiz 3 Review - Questions and Answers The _____ compressor is another positive displacement compressor and is used for larger air conditioning
... [Show More] and refrigeration applications. Screw Compressor The four (4) major components of a vapor compression refrigeration system are the compressor, condenser, evaporator, and ________ ______. Metering device The amount of heat a refrigerant contains with -40F as the 0 heat content reference point is called Enthalpy From a performance standpoint, a substitute for R-12 is R-134A The ___________ __________ is referred to as a kinetic displacement compressor. Centrifugal Compressor The refrigerant vapor picks up additional heat as it flows from the evaporator to the compressor. The heat is picked up from the Suction line What is the purpose of the metering device? Meters the flow of refrigerant entering the evaporator, reduces the boiling point to create a pressure/temperature drop When the refrigerant leaves the metering device, it is not 100% liquid. Why? Because flash gas occurs and causes the 100% liquid to turn into 25% vapor and 75% liquid. Rejects both sensible and latent heat from the refrigeration system. Condenser Abort heat from the system Evaporator Is the heart of the refrigeration system? Compressor A valve or small fixed-size tubing or orifice that meters liquid refrigerant into the evaporator Metering device R-502 Orchid R-12 White R-717 Silver R-11 Orange R-114 Dark Blue R-134a Light Blue R-113 Purple R-500 Yellow Orange R-22 Green Good ventilation is important when working around refrigeration equipment because modern refrigerants ______. Are heavier than air and may displace the oxygen around you The __________ relationship correlates the vapor pressure and the boiling point of water and is the basis for controlling the cooling system's temperatures. Temperature/pressure Which of the following refrigerants has the lowest boiling temperatures at atmospheric pressure? R-502 The compressor in a refrigeration system _______. Pumps the refrigerant throughout the system A ton of refrigeration is equal to 288,000 Btu/24-Hr The law requires technicians to recover refrigerant from all refrigeration systems so that they ________. Will not be released into the atmosphere, May be used again, May be reclaimed for future use. Refrigeration can be described as _______. The process of removing heat from a place where it isn't wanted to place where it makes little or no difference The temperature inside the refrigerator fresh food section should be about _______. 35 degrees F The evaporator in a refrigeration system Absorbs heat from the product to be cooled High temperature refrigeration is that produced by ________. An air conditioning system Reciprocating compressors have A piston and cylinder The condenser Rejects heat from the refrigerant When a refrigerant enters the compressor, it is a ______ and when it leaves the compressor, it is a __________. Low pressure Low temperature super heated vapor, High pressure High temperature super heated vapor The _______________ are used to change the vapor to a liquid and the liquid from back into a vapor the refrigeration cycle. Condenser and evaporator Ice melts in iceboxes because _________. Heat enters when the door is opened, Heat flows through the insulated walls, Heat enters when warm food is placed in the icebox T/F If a cylinder of R-22 is moved from a 100F truck False T/F Modern refrigerators have become state of the art appliances and some models even include automatic beverage and ice dispensers, built in television screens and connections to the World Wide Web. True [Show Less]