UNIT 17 REVIEW QUESTIONS ANSWER KEY GO BACK TO INDEX
17-1) Define refrigerant.
Refrigerant is the fluid used in a refrigeration system for transferring heat.
17-2) What organization has established the number designation for refrigerants?
17-3) What are the chemical components of CFC refrigerant?
17-4) What are the chemical components of HCFC refrigerant?
17-5) What are the chemical components of HFC refrigerant?
17-6) What is ozone?
17-7) Which chemical family of refrigerants has the highest ozone depletion potential?
17-8) What is the primary safety concern when working with R-410A?
17-9) Define the term “glide” when referring to zeotropic refrigerants.
17-10) Explain the ASHRAE refrigerant safety designation regarding refrigerants toxicity
and flammability.
17-11) What is the difference between a disposable refrigerant cylinder and a refillable
refrigerant cylinder?
17-12) What is the difference between a compound and a zoetrope?
17-13) What is the difference between a zoetrope and an azeotrope?
17-14) What contaminants can be found in refrigerant?
17-15) State two reasons ammonia has limited use.
17-16) What refrigerant is being used in small appliances in place of R-12?
17-17) What refrigerant is being used in new air conditioning systems in place of R-22?
HFC-410A
17-18) When working with ammonia, what safety equipment must be available?
17-19) How can the presence of noncondensable material in a refrigerant cylinder be
detected?
17-20) Describe the difference between latent heat and sensible heat and explain why these
concepts are important for a refrigerant.
17-21) What is the difference between a low-pressure refrigerant and a high–pressure
refrigerant?
17-22) Which types of refrigerants are listed as Class I ozone depleting substances by the
EPA?
17-23) What chemical family is the basic building block for most modern refrigerants?
17-24) What is a halogenated refrigerant?
17-25) What effects does water have when introduced in a system with refrigerant?
17-26) What differences are there between handling zeotropes and azeotropes?
17-27) Explain the difference between a bubble point and a dew point.
17-28) What is fractionation and how does it affect the way zeotropic refrigerants are
handled?
17-29) What is the difference between a high-glide blend and a low-glide blend?
17-30) Why do CFCs deplete the ozone layer?
17-31) What is the ozone layer?
17-32) What benefit is the ozone layer to us?
17-33) Why are HCFCs not as harmful to the atmosphere as CFCs?
17-34) What is the difference between ozone depletion and global warming?
17-35) What gas is used as the standard for comparison when assigning a refrigerant’s
global warming potential?
17-36) What has been used for years as a refrigeration lubricant with CFCs and HCFCs?
17-37) What lubricants can be used with HFCs?
17-38) Why should a refrigeration lubricant be miscible with the system refrigerant?
17-39) What is a hygroscopic lubricant?