313D Refrigerant Handling and Recovery 3 — Questions and Answers
Question 1: During system-dependent (passive) recovery, refrigerant is transferred using:
- An external recovery machine compressor
- The system's own compressor to push refrigerant into recovery cylinders (Correct answer)
- A vacuum pump connected to the low side
- Gravity flow from a higher-pressure liquid line
Correct answer: The system's own compressor to push refrigerant into recovery cylinders
System-dependent recovery uses the appliance's own compressor to pump refrigerant into recovery cylinders without an external machine.
Question 2: What evacuation level is required before opening a system for major repairs on equipment manufactured after November 15, 1993, using a recovery machine manufactured after that same date?
- 0 psig
- 4 inches Hg vacuum (Correct answer)
- 10 inches Hg vacuum
- 15 inches Hg vacuum
Correct answer: 4 inches Hg vacuum
For equipment manufactured after November 15, 1993, using a post-1993 recovery machine, the required evacuation level before major repairs is 4 inches of mercury vacuum.
Question 3: R-22 refrigerant recovered from a system and later found to be contaminated must be:
- Blended with virgin R-22 before reuse
- Reclaimed to AHRI 700 purity standards or sent to a certified reclaimer (Correct answer)
- Vented to atmosphere since R-22 is being phased out
- Re-used in any system as long as the refrigerant was recovered legally
Correct answer: Reclaimed to AHRI 700 purity standards or sent to a certified reclaimer
Contaminated refrigerant must be reclaimed to AHRI 700 purity standards by an EPA-certified reclaimer before it can be resold or reused in a different system.
Question 4: A recovery cylinder must be hydrostatically tested and replaced or retested no more than how many years after the original test date stamped on the collar?
- 3 years
- 5 years (Correct answer)
- 7 years
- 12 years
Correct answer: 5 years
DOT-compliant recovery cylinders must be re-qualified (hydrostatically retested) every 5 years from the date stamped on the collar.
Question 5: What is the safest procedure when connecting manifold gauge hoses to recover refrigerant from a potentially pressurized system?
- Open the manifold valves first, then attach hoses to prevent pressure lock
- Attach hoses with valves closed, then slowly open system service valves (Correct answer)
- Purge all hoses with nitrogen before connecting to the system
- Connect the high-side hose last to equalize pressure gradually
Correct answer: Attach hoses with valves closed, then slowly open system service valves
Connecting hoses with manifold valves closed prevents accidental release of refrigerant and controls the rate at which system pressure enters the hoses.
Question 6: Which document must a refrigerant reclaimation facility provide to verify that recovered refrigerant meets AHRI 700 purity standards?
- EPA Form 7630
- Certificate of Reclaim (analysis report) (Correct answer)
- DOT Form HM-181
- Manufacturer's Safety Data Sheet (SDS)
Correct answer: Certificate of Reclaim (analysis report)
A certified reclaimer issues a certificate of reclaim (or analysis report) confirming the refrigerant meets AHRI Standard 700 purity requirements.
Question 7: When transferring liquid refrigerant from a recovery cylinder to a system, the technician should:
- Connect the cylinder vapor port to the system high side
- Invert the cylinder or use the liquid valve to push liquid into the low side (Correct answer)
- Use the recovery machine in reverse to push liquid under pressure
- Connect the cylinder liquid port to the system low side with the cylinder upright
Correct answer: Invert the cylinder or use the liquid valve to push liquid into the low side
Inverting the cylinder or using the dip-tube liquid valve ensures liquid refrigerant flows out; connecting to the high side helps push the charge into the system.
313D Refrigerant Handling and Recovery 3
During system-dependent (passive) recovery, refrigerant is transferred using: