EPA 608 609 Section 609 MVAC Systems 3 — Questions and Answers
Question 1: Which refrigerant replaced R-12 in vehicles manufactured from the mid-1990s?
- R-22
- R-134a (Correct answer)
- R-410A
- R-11
Correct answer: R-134a
R-134a (HFC-134a) replaced R-12 in MVAC systems starting in the mid-1990s.
Question 2: Recovery/recycling equipment for R-12 must meet which standard?
- SAE J1991 (Correct answer)
- ASHRAE 15
- UL 1995
- NFPA 70
Correct answer: SAE J1991
SAE J1991 sets the standard for R-12 recovery and recycling equipment.
Question 3: Why must R-12 and R-134a never be mixed in the same system?
- They are the same chemical
- Cross-contamination damages equipment and recycled refrigerant (Correct answer)
- It improves cooling
- It is required by law to mix them
Correct answer: Cross-contamination damages equipment and recycled refrigerant
Mixing refrigerants cross-contaminates recovery equipment and ruins recycled refrigerant.
Question 4: What fitting design helps prevent accidental mixing of R-12 and R-134a?
- Identical threaded ports
- Unique quick-connect service fittings (Correct answer)
- No fittings at all
- Color-blind connectors
Correct answer: Unique quick-connect service fittings
R-134a uses unique quick-connect fittings that differ from R-12 to prevent cross-charging.
Question 5: The newest low-GWP refrigerant adopted for many modern MVAC systems is:
- R-12
- R-134a
- R-1234yf (Correct answer)
- R-502
Correct answer: R-1234yf
R-1234yf is a low-global-warming-potential refrigerant used in many newer vehicles.
Question 6: Compared to R-134a, R-1234yf is notable for being:
- Highly ozone depleting
- Mildly flammable (A2L) (Correct answer)
- Non-refrigerant
- More damaging to the ozone layer
Correct answer: Mildly flammable (A2L)
R-1234yf is classified A2L, meaning it is mildly flammable, unlike R-134a.
Question 7: Recovery equipment for R-134a is governed by which SAE standard?
- SAE J1991
- SAE J2210 (Correct answer)
- SAE J639
- SAE J1234
Correct answer: SAE J2210
SAE J2210 covers R-134a recovery/recycling equipment for MVAC.
EPA 608 609 Section 609 MVAC Systems 3
Which refrigerant replaced R-12 in vehicles manufactured from the mid-1990s?