MACS 609 Certification Exam UPDATED
QUESTIONS AND CORRECT ANSWERS
The use of ultraviolet (UV) or fluorescent dyes in an HFO-1234yf system is: - CORRECT
ANSWER Approved by some vehicle manufactures but not by others
One effect of some refrigerant gases in the atmosphere is that they: - CORRECT
ANSWER Contribute to trapping heat
Which item is not mentioned in the SAE J2099 Standard of refrigerant purity? - CORRECT
ANSWER Sludge
When it has been determined that an A/C system has a low refrigerant charge, what should be
done? - CORRECT ANSWER Perform a leak test procedure
Which item is not mentioned in the SAE J1991 standard of refrigerant purity? - CORRECT
ANSWER Acid
Which of the following is unlikely to affect refrigerant charge accuracy? - CORRECT
ANSWER A/C Compressor
CFC-12 recovery equipment has SAE 3/8-inch service fittings. HFC-134a recovery
equipment has: - CORRECT ANSWER Quick-couple design
What is the advantage of using refrigerant identification equipment? - CORRECT
ANSWER Allows the ability to determine what type of refrigerant is in system
If an HFC-134a A/C system still has pressure after the first refrigerant recovery process is
complete (including the five-minute pause), additional recovery is necessary until the system
vacuum level remains stable for: - CORRECT ANSWER 2 minutes
, Paid technicians who service or repair buses using HCFC-22 as refrigerant, and/or service or
repair aircraft or ship/boat cargo refrigeration equipment: - CORRECT ANSWER Must
be Section 608 Type II Certified
Specific safety information for managing incidents involving refrigerants and other chemicals
(inhalation, spills, fires, etc.) is found in the: - CORRECT ANSWER Material safety
data sheet (MSDS) for the chemical
To what does Global Warming Potential (GWP) refer? - CORRECT
ANSWER Relative ability to produce global warming effect
When performing engine pre-heat for refrigerant removal, the technician should do ALL of
the following EXCEPT: - CORRECT ANSWER Make sure the compressor is
operating
PAG lubricant: - CORRECT ANSWER Is hygroscopic (absorbs moisture)
Electronic leak detectors certified to SAE J2791 have the capability of identifying leakage
rates as low as: - CORRECT ANSWER Electronic leak detectors certified to SAE
J2791 have the capability of identifying leakage rates as low as:
When using an HFC-134a refrigerant recovery machine, after completing 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
A/C system service equipment hoses must be equipped with shutoff valves located within
_______ from the "vehicle end" of the hoses. - CORRECT ANSWER 12 inches
To what does Ozone Depletion Potential (ODP) refer? - CORRECT ANSWER Relative
ability to destroy ozone
QUESTIONS AND CORRECT ANSWERS
The use of ultraviolet (UV) or fluorescent dyes in an HFO-1234yf system is: - CORRECT
ANSWER Approved by some vehicle manufactures but not by others
One effect of some refrigerant gases in the atmosphere is that they: - CORRECT
ANSWER Contribute to trapping heat
Which item is not mentioned in the SAE J2099 Standard of refrigerant purity? - CORRECT
ANSWER Sludge
When it has been determined that an A/C system has a low refrigerant charge, what should be
done? - CORRECT ANSWER Perform a leak test procedure
Which item is not mentioned in the SAE J1991 standard of refrigerant purity? - CORRECT
ANSWER Acid
Which of the following is unlikely to affect refrigerant charge accuracy? - CORRECT
ANSWER A/C Compressor
CFC-12 recovery equipment has SAE 3/8-inch service fittings. HFC-134a recovery
equipment has: - CORRECT ANSWER Quick-couple design
What is the advantage of using refrigerant identification equipment? - CORRECT
ANSWER Allows the ability to determine what type of refrigerant is in system
If an HFC-134a A/C system still has pressure after the first refrigerant recovery process is
complete (including the five-minute pause), additional recovery is necessary until the system
vacuum level remains stable for: - CORRECT ANSWER 2 minutes
, Paid technicians who service or repair buses using HCFC-22 as refrigerant, and/or service or
repair aircraft or ship/boat cargo refrigeration equipment: - CORRECT ANSWER Must
be Section 608 Type II Certified
Specific safety information for managing incidents involving refrigerants and other chemicals
(inhalation, spills, fires, etc.) is found in the: - CORRECT ANSWER Material safety
data sheet (MSDS) for the chemical
To what does Global Warming Potential (GWP) refer? - CORRECT
ANSWER Relative ability to produce global warming effect
When performing engine pre-heat for refrigerant removal, the technician should do ALL of
the following EXCEPT: - CORRECT ANSWER Make sure the compressor is
operating
PAG lubricant: - CORRECT ANSWER Is hygroscopic (absorbs moisture)
Electronic leak detectors certified to SAE J2791 have the capability of identifying leakage
rates as low as: - CORRECT ANSWER Electronic leak detectors certified to SAE
J2791 have the capability of identifying leakage rates as low as:
When using an HFC-134a refrigerant recovery machine, after completing 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
A/C system service equipment hoses must be equipped with shutoff valves located within
_______ from the "vehicle end" of the hoses. - CORRECT ANSWER 12 inches
To what does Ozone Depletion Potential (ODP) refer? - CORRECT ANSWER Relative
ability to destroy ozone
