EPA 608 609 609 3 — Questions and Answers
Question 1: Which refrigerant replaced R-12 in most vehicles built in the mid-1990s and later?
- R-134a (HFC-134a) (Correct answer)
- R-22
- R-404A
- R-507
Correct answer: R-134a (HFC-134a)
R-134a became the standard MVAC refrigerant after R-12 was phased out.
Question 2: What is the newer low-GWP refrigerant being adopted in modern MVAC systems?
- R-1234yf (HFO) (Correct answer)
- R-410A
- R-32
- R-290
Correct answer: R-1234yf (HFO)
R-1234yf is a hydrofluoroolefin with very low global warming potential used in newer vehicles.
Question 3: Why is it illegal to knowingly vent R-134a from an MVAC system into the atmosphere?
- It is a potent greenhouse gas prohibited from venting under the Clean Air Act (Correct answer)
- It is explosive at room temperature
- It is acutely toxic to humans
- It corrodes recovery equipment
Correct answer: It is a potent greenhouse gas prohibited from venting under the Clean Air Act
R-134a has a high global warming potential, and venting it violates the Clean Air Act.
Question 4: Before connecting recovery equipment, why must a technician identify the refrigerant in the system?
- To avoid cross-contaminating recovery equipment with mixed refrigerants (Correct answer)
- To set the cabin temperature
- To determine the vehicle's mileage
- To verify the warranty status
Correct answer: To avoid cross-contaminating recovery equipment with mixed refrigerants
Identifying refrigerant prevents cross-contamination of recovery and recycling equipment.
Question 5: What instrument is recommended to confirm the type and purity of refrigerant in a vehicle?
- A refrigerant identifier (Correct answer)
- A multimeter
- A manometer
- A torque wrench
Correct answer: A refrigerant identifier
A refrigerant identifier confirms refrigerant type and detects contamination before service.
Question 6: Refrigerant containers used to store recovered MVAC refrigerant must be which color or marked for the specific refrigerant?
- DOT-approved containers labeled for the specific refrigerant (Correct answer)
- Any clean steel drum
- Open-top buckets
- Glass jars
Correct answer: DOT-approved containers labeled for the specific refrigerant
Recovered refrigerant must be stored in DOT-approved containers labeled for that refrigerant.
Question 7: What happens to a vehicle's R-12 system that is being retrofitted to R-134a?
- It must use unique service fittings and proper labeling to prevent cross-contamination (Correct answer)
- It can use the same fittings as R-12
- It no longer needs recovery equipment
- It can be vented during conversion
Correct answer: It must use unique service fittings and proper labeling to prevent cross-contamination
Retrofits require unique service fittings and labels to avoid mixing R-12 and R-134a.
EPA 608 609 609 3
Which refrigerant replaced R-12 in most vehicles built in the mid-1990s and later?