MACS 609 Certification ACTUAL EXAM
2026/2027: 100% Verified Questions &
Correct Answers
Question 1: During refrigerant recovery from a mobile A/C system, a technician notices the
compressor is not engaging. What is the FIRST step to ensure proper refrigerant recovery?
A. Immediately replace the compressor clutch
B. Check electrical connections and verify power to the compressor clutch
C. Add more refrigerant to the system
D. Use a recovery machine with higher capacity
Correct Answer: B
Rationale: According to EPA Section 609 regulations, technicians must verify electrical connections
and power supply before assuming component failure, as electrical issues are the most common
cause of compressor non-engagement.
Question 2: When recovering refrigerant from a vehicle equipped with an orifice tube system, what
is the MINIMUM recovery efficiency required by EPA regulations?
A. 80%
B. 85%
C. 90%
D. 95%
Correct Answer: C
, Rationale: EPA Section 609 requires a minimum of 90% recovery efficiency for orifice tube systems,
which is higher than the 80% required for expansion valve systems due to their different operating
characteristics.
Question 3: A technician is servicing a 2025 hybrid vehicle with an electric compressor. Which
safety precaution is MOST critical before beginning refrigerant service?
A. Disconnect the 12-volt battery only
B. Isolate and lockout the high-voltage system following manufacturer procedures
C. Remove the main fuse
D. Ground the vehicle chassis
Correct Answer: B
Rationale: Hybrid and electric vehicles require specific high-voltage lockout procedures to prevent
electrical shock, which must be followed in addition to standard refrigerant handling safety
protocols.
Question 4: What is the MAXIMUM allowable refrigerant leak rate per year for passenger car mobile
A/C systems under EPA regulations?
A. 10% of the total system charge
B. 15% of the total system charge
C. 20% of the total system charge
D. 25% of the total system charge
Correct Answer: A
Rationale: EPA regulations specify that mobile A/C systems should not leak more than 10% of their
total refrigerant charge annually to minimize environmental impact and maintain system efficiency.
Question 5: When using a recovery machine with a filter-drier, how often should the filter-drier be
replaced according to best practices?
A. Every 6 months
2026/2027: 100% Verified Questions &
Correct Answers
Question 1: During refrigerant recovery from a mobile A/C system, a technician notices the
compressor is not engaging. What is the FIRST step to ensure proper refrigerant recovery?
A. Immediately replace the compressor clutch
B. Check electrical connections and verify power to the compressor clutch
C. Add more refrigerant to the system
D. Use a recovery machine with higher capacity
Correct Answer: B
Rationale: According to EPA Section 609 regulations, technicians must verify electrical connections
and power supply before assuming component failure, as electrical issues are the most common
cause of compressor non-engagement.
Question 2: When recovering refrigerant from a vehicle equipped with an orifice tube system, what
is the MINIMUM recovery efficiency required by EPA regulations?
A. 80%
B. 85%
C. 90%
D. 95%
Correct Answer: C
, Rationale: EPA Section 609 requires a minimum of 90% recovery efficiency for orifice tube systems,
which is higher than the 80% required for expansion valve systems due to their different operating
characteristics.
Question 3: A technician is servicing a 2025 hybrid vehicle with an electric compressor. Which
safety precaution is MOST critical before beginning refrigerant service?
A. Disconnect the 12-volt battery only
B. Isolate and lockout the high-voltage system following manufacturer procedures
C. Remove the main fuse
D. Ground the vehicle chassis
Correct Answer: B
Rationale: Hybrid and electric vehicles require specific high-voltage lockout procedures to prevent
electrical shock, which must be followed in addition to standard refrigerant handling safety
protocols.
Question 4: What is the MAXIMUM allowable refrigerant leak rate per year for passenger car mobile
A/C systems under EPA regulations?
A. 10% of the total system charge
B. 15% of the total system charge
C. 20% of the total system charge
D. 25% of the total system charge
Correct Answer: A
Rationale: EPA regulations specify that mobile A/C systems should not leak more than 10% of their
total refrigerant charge annually to minimize environmental impact and maintain system efficiency.
Question 5: When using a recovery machine with a filter-drier, how often should the filter-drier be
replaced according to best practices?
A. Every 6 months
