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MACS 609 CERTIFICATION QUESTIONS
WITH CORRECT ANSWERS
Question :Before reuse, what must be done with HFC-134a
that has been recovered from a mobile A/C system using recovery-only equipment?
Question 2 options:
Recycle the HFC-134a before reuse using certified equipment
Correct answer:Recycle the HFC-134a before reuse using
certified equipment
Question :Which type of tank must be used during the transfer
of refrigerant?
Question 10 options:
Tanks marked DOT 4BA
Correct answer:Tanks marked DOT 4BA
Question :If lubricant is removed by recovery equipment
during system refrigerant removal, what must be done with the lubricant?
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Correct answer:Re-install lubricant removed by the recovery
equipment
Question :When can HFC-134a become combustible in a
mobile air conditioning system?
Correct answer:If shop air is used in the system in an attempt
to check for leaks and HFC-134a is present
Question :Which type of mobile A/C system will usually
require additional time / precautions to extract all the refrigerant?
Correct answer:Accumulator type
Question :Electronic leak detectors certified to SAE J2791
have the capacity of identifying leakage rates as low as:
Correct answer:0.15 ounces per year
Question :When recovery/recycling equipment is used to
remove refrigerant from a mobile A/C system, how much lubricant will be removed during the operation?
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Correct answer:Generally, very little, if any
Question :Why is it necessary to insure that service port caps
containing good seals are installed?
Correct answer:To minimize refrigerant loss
Question :Which of the following statements is correct about
flushing A/C systems?
Correct answer:Flushing solvents may remain in A/C systems,
causing problems
Question :When using an HFC-134a refrigerant recovery
machine, after competing the first recovery process, how long must you wait, then check the machine's gauges for a rise in pressure above vacuum, which would indicate that the system still contains some refrigerant?
Correct answer:5 minutes
Question :When it has been determined that an A/C system
has a low refrigerant charge, what should be done?
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Correct answer:Perform a leak detection procedure
Question :One effect of some refrigerant gases in the
atmosphere is that they:
Correct answer:Contribute to trapping heat
Question :Mixing CFC-12 and HFC-134a in the same system
will:
Correct answer:Result in refrigerant cross contamination
Question :How much moisture is removed from a mobile A/C
system during a typical evacuation?
Correct answer:Possibly none
Question :Paid technicians who service or repair mobile A/C
systems using HFC-22 as refrigerant, or service cargo