HVAC Refrigerant Recovery and Handling 2 — Questions and Answers
Question 1: What is the maximum allowable leak rate for refrigerant systems with a charge over 50 lbs in comfort cooling applications under EPA Section 608?
- 5% per year
- 10% per year
- 15% per year (Correct answer)
- 20% per year
Correct answer: 15% per year
EPA Section 608 sets the leak rate trigger at 15% of the total charge per year for comfort cooling equipment with charges over 50 lbs.
Question 2: Which refrigerant blend requires special 'push-pull' recovery techniques due to its zeotropic behavior causing fractionation?
- R-410A
- R-22
- R-404A (Correct answer)
- R-134a
Correct answer: R-404A
R-404A is a zeotropic blend whose components can separate (fractionate) during recovery, making push-pull or liquid-phase recovery preferable.
Question 3: A technician recovers refrigerant into a cylinder that already contains a different refrigerant. What must happen to this cylinder?
- It can be sent to a reclamation facility as-is
- It must be labeled as mixed/contaminated and sent to a refrigerant reclaimer (Correct answer)
- It must be vented immediately to prevent pressure buildup
- It can be reused after checking pressure
Correct answer: It must be labeled as mixed/contaminated and sent to a refrigerant reclaimer
Mixing refrigerants creates a contaminated blend that cannot be reused and must be sent to a certified reclaimer for proper disposal.
Question 4: What does a 'two-stage' recovery machine do differently than a single-stage unit?
- It uses two separate refrigerant circuits to increase speed
- It recovers vapor first then switches to liquid recovery automatically (Correct answer)
- It can recover two different refrigerants simultaneously
- It uses two condensers to lower discharge temperature
Correct answer: It recovers vapor first then switches to liquid recovery automatically
A two-stage recovery machine first removes vapor refrigerant, then automatically switches to remove liquid refrigerant for more complete recovery.
Question 5: Under EPA Section 608, technicians working on small appliances (systems with 5 lbs or less of refrigerant) must recover what percentage of refrigerant when using a non-self-contained recovery device?
- 60%
- 70%
- 80%
- 90% (Correct answer)
Correct answer: 90%
When using a non-self-contained recovery device on small appliances, technicians must recover 90% of the refrigerant.
Question 6: What is the primary purpose of an oil separator used during refrigerant recovery?
- To remove moisture from the refrigerant before storage
- To separate compressor oil from refrigerant before it enters the recovery cylinder (Correct answer)
- To filter acid from contaminated refrigerant
- To regulate pressure entering the recovery machine
Correct answer: To separate compressor oil from refrigerant before it enters the recovery cylinder
An oil separator prevents compressor oil from entering the recovery cylinder, keeping the refrigerant cleaner and reducing contamination.
Question 7: Which condition requires a technician to evacuate a recovery cylinder before reusing it for the same refrigerant?
- When the cylinder has been stored outdoors
- When the residual pressure is above atmospheric
- When the cylinder contains a different refrigerant or is contaminated (Correct answer)
- When the cylinder's last fill date was over 30 days ago
Correct answer: When the cylinder contains a different refrigerant or is contaminated
A recovery cylinder must be evacuated before reuse if it contains a different refrigerant or any contamination to prevent cross-contamination.
HVAC Refrigerant Recovery and Handling 2
What is the maximum allowable leak rate for refrigerant systems with a charge over 50 lbs in comfort cooling applications under EPA Section 608?