Why should long hoses between the unit and the recovery machine be avoided?

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multiple passes through devices, such as replaceable core filter-driers, which reduce moisture, acidity, andparticulate matter.Recycled refrigerant may be charged into the same system or another system with thesame ownership. Recycling equipment must meet AHRI 740 Performance Rating Standard.Reclaimmeans to process refrigerant to a level equal to new (virgin) product specifications as determined bychemical analysis.Reclaimed refrigerants must meet AHRI 700 Standards, before it can be sold.This isnormally preformed at a chemical processing company.Recovery DevicesRefrigerant recovery and/or recycling equipment manufactured after November 15, 1993 must be certified andlabeled by an EPA-approved equipment testing organization to meet EPA standards.An EPA-approvedcertification label is required on all new recovery equipment.There are two basic types of recovery devices:“System-dependent”(passive) which captures refrigerant withthe assistance of components in the appliance from which refrigerant is being recovered, Figure 7."Self-contained”(active) which has its own means to draw the refrigerant out of the appliance, Figure 8.The recovery time will be increased if the appliance is located in low ambient temperatures or long hoses areused between the unit and the recovery machine.Long and small diameter hoses between the unit andrecovery machine should be avoided as they will cause excessive pressure drop and increase recovery time.Upon completion of refrigerant liquid transfer between recovery unit and the refrigeration system, guardagainst trapping liquid refrigerant in the service hose between closed service valves.The technician must have a separate refrigerant recovery cylinder for each type of refrigerant recovered andshould have a separate cylinder for refrigerants known to be mixed.If servicing systems that useHFC-134a, HFC-410A and HCFC-22, then three cylinders are required even though two are HFCs.It isimportant not to mix refrigerants in the same container when recovering as refrigerants that are mixed be maybe impossible to reclaim and there may be an added cost to have them destroyed.Technicians can only charge used CFC, HCFC, or HFC refrigerants back into the same appliance or intoanother appliance with the same owner.Used refrigerant may no longer meet the AHRI standard for virginrefrigerant so it cannot change ownership without being reclaimed.Figure 7. Passive Recovery Bag 12 oz or less.Figure 8. Active Recovery Unit. Courtesy of Appion Inc.

1. What type of refrigerant is chlorine free?

   HFC's

2. Refrigerant migrates to the compressor crankcase because of a difference in ________ between the refrigerant and the oil

   vapor pressure

3. Which refrigerant is an HCFC? R-22, R-134a, R-410a, R-12

   R- 22

4. Which Refrigerant is an HCFC? R-124, R-134A, R410a, R-12

    R-124

5. What factor(s) affects the speed of evacuation?

   • A) the size of the equipment being evacuated
   • B) the ambient temperature
   • C) the amt of moisture in the system

6. Systems charged with R-134a should be leak checked with:

    pressurized dry nitrogen

7. HCFC refrigerants contain:

    hydrogen, chlorine, fluorine, carbon

8. Manifold gauge sets are often color coded, when this is done, the low pressure gauge is color coded:

    blue

9. After refrigerant liquid transfer between recovery unit and the system being emptied, you need to avoid trapping:

    liquid refrigerant between service valves

10. When can you use a disposable cylinder to recover refrigerant?

     never

11. CFC refrigerants are so named because they contain the elements:

     chlorine, fluorine, carbon

12. Recovery equipment that relies upon the compressor in the system would be considered:

     system-dependant

13. The EPA requires the installation of a service aperture stub on all appliances using a class I or class II sustance as a refrigerant. The main purpose of this requirement is to make it easier to:

     recover refrigerant

14. When dealing with small systems, how many different refrigerants may be recovered in the same cylinder?

     only one

15. It is important not to mix different refrigerants in the same container because:

     the mixture may be impossible to reclaim

16. Chlorofluorocarbons (CFC's) and hydrochlorofluorocarbons (HCFC's) have which of the following in common?

     they must be recovered before opening or disposing of appliances

17. Refrigerant that is recovered can be returned to:

     the same system or other systems owned by the same person without restrictions

18. An example of a HFC refrigerant is:

     R-134a

19. When transporting cylinders containing used refrigerant, the DOT requires that you:

     attach DOT classification tags

20. Blended refrigerants leak from a system:

     in uneven amounts due to different vapor pressures

21. Which type of refrigerant is the most harmful to stratospheric ozone?

     CFC

22. Long hoses between the unit and the recovery machine should not be used because they cause:

    • A) excessive pressure drop
    • B) increased recovery time
    • C) Increased emissions

23. If corrosion is found within the body of a relief valve, the valve must be:

     replaced

24. Disposable refrigerant containers are used for ______ refrigerant.

    C) virgin

25. Never use an open flame to heat a refrigerant tank because

    • A) it can result in venting refrigerant to the atmosphere
    • B) the tank may explode, causing serious injury to people nearby
    • C) refrigerant in the tank may decompose, forming a toxic material

26. If an oil is hygroscopic it means that it:

     readily absorbs moisture

27. The type of oil that is most commonly used in stationary refrigeration applications w/ HFC-134a refrigerant is:

    ester oil

28. Which type of refrigerant is the most harmful to stratospheric ozone?

    refrigerants containing bromine

29. Ozone depletion in the Stratosphere is what type of problem?

    global

30. Under EPA's regulations, what standard must reclaimed refrigerant meet before it can be resold?

    ARI 700

31. Under the EPA's " safe disposal requirements ", who is responsible of making sure that the refrigerant is removed from household refrigerators before they are disposed of:

    final person in the disposal chain

32. Ozone depletion potential, or "ODP," is

    a measure of the ability of CFCs' and HCFCs' to destroy ozone

33. _______ is the process of removing refrigerant in any condition from a system and storing it in a container without necessarily testing or processing it in any way.

    recovering

34. The EPA can require a technician to demonstrate their ability to perform proper procedures for recovering and/or recycling refrigerant. Failure to demonstrate competency can result in:

    revocation of the technician's certification

35. Never use oxygen or compressed air to pressurize a system because:

    when mixed with compressor oil or some refrigerants, it could explode

36. Which of the following is an approved "drop-in" service replacement for R-12? HFC-134a, HFC-410a, R-407c, according to the EPA there are no "drop-in" replacements

    according to the EPA there are no "drop-in" replacements

37. The synthetic lubricant presently used with ternary blends containing HCFCs is 

    alkybenzene

38. On a typical three port ( three hose) manifold gauge, the center port is used for:

    recovery, evacuation and charging

39. What refrigerant type has the highest ozone depletion potential?  HCFCs, HFCs, CFCs

    CFCs

40. What refrigerant has the lowest ozone depletion potential? R-22, R-11, R-12, or R-113

    R-22

41. Which refrigerants must be recovered before opening a system or disposing of a system?

    all refrigerants must be recovered

42. When dehydrating a system, the system can be heated to

    decrease the dehydration time

43. Use _______ to remove ice from the sight glass.

    an alcohol spray

44. What atom of the CFC molecule causes ozone depletion?

    chlorine

45. Refrigerant vapors or mist should not be inhaled because:

    they may cause heart irregularities and/or unconsiousness

46. The high pressure gauge on service manifold sets has a continuous scale, usually calibrated to read from:

    0-500psi

47. P.P.E.'s (gloves, safety glasses, safety shoes, etc.) should always be worn is when:

    handling and filling cylinders

48. "Self-contained" recovery devices:

    can capture liquid and/or vapor refrigerant without the assistance of components in the air-conditioning or refrigeration equipment

49. It is necessary to place a refrigerant label on:

    a refrigerant cylinder which is being returned for reclaiming

50. Before you dispose of any system containing a refrigerant, you must:

    recover the refrigerant

51. Refrigerant leaves the condenser of an operating system as a:

    high pressure liquid

52. Non-Azeotropic refrigerants leak from a system:

    in uneven amounts due to different vapor pressures

53. Whe using nitrogen to pressurize a system, you should always:

    charge through a pressure regulator

54. All recovery equipment currently being made is required to have

    an EPA approved certification label

55. The color code for approved refrigerant recovery cylinders is 

    yellow tops and gray bodies

56. All devices used for refrigerant recovery must:

    meet EPA standards

57. Which of the following gases help form the earth's protective shield? chlorine, chlorides, carbon monoxide, stratosphere ozone

    stratosphere ozone

58. Refrigerant cylinders should always be:

    • A) free of rust and damage
    B) color coded to indicate the contents
    C) secure

59. It is illegal to:

    knowingly release any refrigerant during the service, maintenance, repair or disposal of appliances, with the exception of de minimis releases

60. When using nitrogen in a system, when is it a violation of the EPA prohibition on venting?

    release of mixtures of nitrogen and refrigerant that result from adding nitrogen to a fully charged appliance to "leak-check" the appliance

61. An award of up to what amount may be paid to a person supplying information that leads to a penalty against the technician who is intentionally venting?

    $10,000

62. Ester based oils can be mixed with:

    no other oils

63. Recycling and recovery equipment intended for use with air-conditioning and refrigeration equipment (except for small appliances) must be tested under:

    ARI 740

64. A compound pressure gauge, typically used on the low side of the system, measures pressure in:

    psig and inches of mercury

65. Which of the following human health effects could result from an increase in ultraviolet radiation?

    an increase in cataracts cases

66. When a system will not hold a vacuum after it has been evacuated, then:

    the system may be leaking

67. You can determine safe pressure for leak testing a system from the:

    low-side test-pressure data-plate value

68. Systems charged with R-410a should be leak checked with:

    pressurized nitrogen

69. Which chemicals are controlled by the Montreal Protocol? chlorofluorocarbons, hydrochlorofluorocarbons, halons

    chlorofluorocarbons, hydrochlorofluorocarbons, halon

70. After 1995, any supplies of CFC refrigerant to service existing units in the USA can only come from:

    recovery and recycling

71. A ternary refrigerant blend is a ____ part mixture. two, three, four or five

    three 

72. Reusable refrigerant containers that are normally under any pressure above 15 psig, must be hydrostatically tested and date stamped every:  1yr, 2yr, 3yr or 5yr

    5 years

73. Refrigerant recovery during low ambient temperatures will:

    slow the recovery process

74. What characteristic(s) of CFCs make them more likely to reach the stratosphere than most other compounds containing chlorine?

    refrigerants that contain chlorine but not hydrogen are so stable that they do not break down in the lower atmosphere after being released. the chlorine or bromine reacts with ozone, causing it to change back to oxygen, thus destroying the ozone layer.

75. A system is dehydrated to:

    remove water and water vapor

76. What refrigerant listed is a "low-pressure refrigerant" under EPA's refrigerant recycling regulations?  R-22, R-123, R-134a or R-500

    R-123

77. Which of the following is a "high-pressure refrigerant" under EPA's refrigerant recycling regulations?  R-11, R-22, R-113 or R-123

    R-22

78. When dealing with small systems, how many different refrigerants may be recovered into the same cylinder?

    only one

79. The evacuation of a system is a method of:

    dehydration

80. This chemical was found in the upper stratosphere and that indicates that the ozone layer is being destroyed.  chlorine monoxide, carbon monoxide, carbon dioxide, or nitrogen dioxide

    chlorine monoxide

81. Which refrigerant contains a CFC?  R-12, R-22, R-134a, R-410a

    R-12

82. According to the EPA, of the refrigerants listed below, which types of refrigerants will not contribute to global warming?  CFCs, HCFCs, HFCs, the all contribute to global warming

    they all contribute to global warming

83. According to the EPA, an oil sample should be taken for which of the following reasons? a new filter-drier has been installed, the system had a leak or a major component failure, system not cooling properly, recycled refrigerant was added to the system

    the system had a leak or a major component failure

84. A refillable refrigerant cylinder must never be filled to more than _______ of its capacity by weight:

    80%

85. Which of the following is a "very high-pressure refrigerant" under EPA's refrigerant recycling regulations?  R-22, R-134a, R-13, R-500

    R-13

86. In a vapor compression refrigeration system, cooling occurs when:

    refrigerant liquid turns to a vapor

87. What statement is true about an azeotropic refrigerant mixture? it is always made from just two components., it ha a pressure-temperature curve identical to one of its components., it is a mixture that is always made from at least three component refrigerants., it is a mixture that acts like a single-component refrigerant over its entire range.

    It is a mixture that acts like a single-component refrigerant over its entire range

88. What is one of the most serious results of damage to the ozone layer?

    increase in human skin cancer

89. When moisture exists in an operating system, which of the following is the most likely to occur? copper tubes and fittings will rust, compressor discharge valves will freeze up, acid will form, compressor head pressures will rise

    acid will form

90. Each chlorine atom in the stratosphere ca destroy ______ ozone molecules.

    100,000

91. State and local governments can make state laws that:

    • follow the clean air act/EPA regulations
    contain stricter regulations than the clean air act/EPA regulations

92. It is important not to mix R-22 and R-410a refrigerants in the same container because

    the mixture may be impossible to reclaim

93. The term used to describe the fact that a refrigerant blend has a range of boiling or condensing points at a constant pressure is:

    temperature glide

94. To scrap a disposable cylinder, the internal cylinder pressure should be reduced to at least:

    0 psig

95. What is the best proof that CFCs are in the stratosphere?

    measurement of CFCs in air samples from stratosphere

96. During servicing of a refrigeration system containing R-22, the refrigerant must be:

    recovered

97. Which of the following statements would be considered good service practices for conserving refrigerant? recover or recycle refrigerant, keep systems tight, find and repair leaks

    • recover or recycle refrigerant
    keep systems tight
    find and repair leaks

98. Data shows that chlorine in the stratosphere comes mainly from CFCs rather than from natural sources such as volcanoes because:

    the rise in the amount of chlorine in the stratosphere matches the rise in the amount of fluorine, which has different natural sources than chlorine., the rise in the amount of chlorine in the stratosphere matches the rise in CFC emissions., air samples taken from the stratosphere over erupting volcanoes shows that the volcanoes contribute a small quantity of chlorine to the stratosphere when compared to CFC's

99. It has been illegal to vent substitutes for CFC and HCFC refrigerants since:

    november 1995

100. According to ASHRAE's 1992 refrigerant safety classification, which of the following designations would be the most safe? A-1, 
     A-3, B-1, B-3

     A-1

101. In general, blended refrigerants should be charge:

     as a liquid

102. Equipment covered by EPA regulations include

     all air-conditioning and refrigeration equipment using CFC, HCFC of HFC refrigerants

103. Which atom of the CFC molecule causes ozone depletion? fluorine, chlorine, sodium, helium

     chlorine

104. The proper method of discarding a disposable refrigerant cylinder is to:

     assure that all refrigerant is recovered and that the cylinder is rendered useless, then recycle the metal

105. A hermetic compressor must never be operated when:

     there is a dehydration vacuum in the system

106. Of the items listed below, which is (are) violation(s) of the clean air act? falsifying or failing to keep required records. failing to reach required evacuation levels before opening or disposing of appliances., knowingly releasing CFC or HCFC refrigerants or their substitutes while preparing appliances

     all of the above

107. When evacuating a system, the hoses should be:

     as short in length and as large in diameter as possible

108. To obtain an accurate vacuum readings during system evacuation, the system vacuum gauge should be located:

     as far from the vacuum pump as possible

109. Refrigerant that enters the expansion or throttling device (also known as the metering device) is a: saturated vapor, superheated vapor, mixture of vapor and liquid, liquid

     liquid

110. Even though R-22 is considered non-toxic, it:
     is lighter than air, can cause asphyxia, is a class I refrigerant, can be detected by its color

     can cause asphyxia

111. R-410A is not a typical blended refrigerant because:  it is a near azeotropic refrigerant., it can be charged as either a liquid or vapor., while it has a 400 series refrigerant number it behaves like a 500 series refrigerant

     all of the above are true

112. Never overfill refrigerant storage cylinders because:

     the internal pressure of the cylinders may rise in heated areas and cause an explosion

113. Of the refrigerants listed below, which has the lowest ozone depletion potential?  R-22, R-11, R-12, R-113

     R-22

114. Which refrigerant contains a CFC? R-500, R-410A, R-134A, R123

     R-500

115. Which refrigerant is an HCFC?  R-123, R-134A, R-410A, R-12

     R-123

116. Of the refrigerants listed, which has the lowest ozone depletion potential? R-22, 
     R-123, R-134A, R-502

     R-134A

117. "Self-contained" recovery devices:

     can capture liquid and/or vapor refrigerant without the assistance of components in the air-conditioning or refrigeration equipment

118. The Montreal Protocol is:

     a treaty among nations that controls production of CFCs and HCFCs

119. What gas(es) would cause the least damage to the environment during a leak check? dry nitrogen and R-22, dry nitrogen and R-12, compressed air and R-12, dry nitrogen

     dry nitrogen

120. According to the EPA, a _______ leak detection method is considered to be the most effective for locating the general area of a small leak.

     electronic or ultrasonic tester

121. Measuring the system's final vacuum is always done with:

     the system isolated and the vacuum pump heated

122. Which safety precaution(s) should always be followed: never apply an open flame to a refrigerant cylinder, never cut or weld any refrigerant line when refrigerant is in the line, never use oxygen to purge lines or to pressurize a system

     all of the above

123. If a technician has a system where some R-502 was added to an R-22 system. The technician should:

     recover all the refrigerant into a separate tank

124. What refrigerant(s) must be recovered before opening a system or disposing of a system?

     all refrigerants must be recovered

125. During servicing of a refrigeration system containing R-12, the refrigerant must be: 

     recovered

126. Refrigerant that enters the compressor, under normal operating conditions, is a:

     low pressure vapor

127. According to the EPA, when dealing with customer complaints regarding additional costs due to refrigerant recovery efforts, the technician should:

     • explain that refrigerant recovery is necessary to protect human health and the environment
     explain that refrigerant recovery is required by federal(and in some cases state and local) laws
     inform the customer that professional service personnel are duty bound to follow the law and to protect the evvironment

128. Refrigerant entering the compressor of a refrigeration system is a:

     superheated vapor

129. According to EPA regulations, which of the following procedures is not an approved technique for system cleanup after a burnout?
     Installing a suction-line filter-drier, flushing with liquid refrigerant to clean tubing, triple evacuation, deep vacuum evacuation

     flushing with liquid refrigerant to clean tubing

Why should long hoses between the union and the recovery machine be avoided?

What will using long hoses during the recovery process result in?

What is one of the most serious results of damage to the ozone layer?

What are recommended safe work practices when recovering refrigerants?