HVAC Refrigerant Recovery and Handling 4 — Questions and Answers
Question 1: What is 'refrigerant banking' in the context of EPA Section 608 compliance?
- Storing excess refrigerant for future use in the same customer's equipment
- Selling recovered refrigerant to other contractors without reclamation
- Holding recovered refrigerant in approved cylinders for later use or sale (Correct answer)
- Transferring refrigerant between cylinders to maximize storage space
Correct answer: Holding recovered refrigerant in approved cylinders for later use or sale
Refrigerant banking refers to storing recovered refrigerant in approved cylinders—either for reuse in the same system or for sending to a reclaimer.
Question 2: A system using R-22 has been retrofitted with a drop-in replacement. When recovering refrigerant from this system, what special consideration applies?
- The replacement refrigerant can be mixed with R-22 in the same recovery cylinder
- The replacement refrigerant must be recovered into a separate, clearly labeled cylinder (Correct answer)
- No special consideration is needed if the replacement is an HFC blend
- The system must be flushed with nitrogen before recovery begins
Correct answer: The replacement refrigerant must be recovered into a separate, clearly labeled cylinder
Retrofit refrigerants must be recovered separately from R-22 to prevent contamination and ensure each can be properly reclaimed or reused.
Question 3: What is the function of a 'passive' or 'system-dependent' recovery device?
- It uses the system's own compressor to push refrigerant into the recovery cylinder (Correct answer)
- It uses gravity to drain refrigerant from elevated systems
- It automatically stops recovery when the cylinder reaches 80% capacity
- It monitors system pressure and triggers recovery automatically
Correct answer: It uses the system's own compressor to push refrigerant into the recovery cylinder
A passive (system-dependent) recovery device uses the system's own compressor to assist moving refrigerant into the recovery cylinder, requiring no separate recovery machine motor.
Question 4: What is the EPA-required maximum allowable standing vacuum level before a technician can open a system for service on appliances with charges between 200 lbs and 2,000 lbs of HCFC refrigerant?
- 0 psig (atmospheric pressure)
- 4 inches Hg vacuum (Correct answer)
- 10 inches Hg vacuum
- 15 inches Hg vacuum
Correct answer: 4 inches Hg vacuum
For systems with HCFC charges between 200 lbs and 2,000 lbs, EPA requires recovery to 4 inches Hg vacuum before the system can be opened.
Question 5: Which of the following best describes a 'critical leak' as defined by updated EPA Section 608 regulations for industrial process refrigeration?
- Any leak that causes oil contamination
- A leak exceeding 20% of charge per year
- A leak exceeding 30% of charge per year (Correct answer)
- Any leak that triggers a low-pressure safety cutout
Correct answer: A leak exceeding 30% of charge per year
For industrial process refrigeration, the EPA defines a critical leak as one exceeding 30% of total refrigerant charge per year.
Question 6: When using a recovery machine, why is it important to recover liquid refrigerant before vapor whenever possible?
- Liquid recovery is safer because it prevents flash evaporation
- Liquid recovery is significantly faster since more mass is moved per cycle (Correct answer)
- Liquid refrigerant contains fewer contaminants than vapor
- Liquid recovery prevents the recovery machine's compressor from overheating
Correct answer: Liquid recovery is significantly faster since more mass is moved per cycle
Recovering liquid refrigerant is much faster because liquid is denser—you move far more refrigerant mass per unit of time compared to vapor recovery.
Question 7: A DOT 4BA recovery cylinder has a tare weight of 14 lbs stamped on the collar. The current total weight is 50 lbs. What is the net refrigerant weight in the cylinder?
- 36 lbs (Correct answer)
- 50 lbs
- 64 lbs
- 14 lbs
Correct answer: 36 lbs
Net refrigerant weight equals total weight minus tare weight: 50 lbs − 14 lbs = 36 lbs of refrigerant.
HVAC Refrigerant Recovery and Handling 4
What is 'refrigerant banking' in the context of EPA Section 608 compliance?