CFC Refrigerant Handling & Recovery Procedures 5 — Questions and Answers
Question 1: What is the purpose of the 'liquid recovery' method versus 'vapor recovery' when recovering refrigerant?
- Liquid recovery is faster because it transfers refrigerant mass more quickly (Correct answer)
- Vapor recovery is faster because it operates at lower pressure
- Liquid recovery is only used for flammable refrigerants
- Vapor recovery must always be performed before liquid recovery
Correct answer: Liquid recovery is faster because it transfers refrigerant mass more quickly
Liquid recovery transfers refrigerant mass much faster than vapor recovery because liquid is denser, significantly reducing recovery time for large systems.
Question 2: Which of the following conditions would cause a recovery machine to short-cycle (rapid on/off cycling)?
- A fully charged recovery cylinder
- Non-condensable gases in the refrigerant
- A kinked recovery hose restricting refrigerant flow (Correct answer)
- A low refrigerant charge in the system being recovered
Correct answer: A kinked recovery hose restricting refrigerant flow
A kinked or restricted recovery hose causes the recovery machine compressor to short-cycle because it cannot pull adequate refrigerant flow.
Question 3: Under EPA Section 608, technicians working on small appliances (less than 5 lbs of refrigerant) must use recovery equipment that captures at least what percentage of refrigerant?
- 60%
- 70%
- 80%
- 90% (Correct answer)
Correct answer: 90%
EPA requires recovery equipment certified to capture at least 90% of the refrigerant from small appliances before disposing of or opening the system.
Question 4: What does the term 'recycle' mean in the context of refrigerant handling, as distinct from 'reclaim'?
- Recycle means venting refrigerant to the atmosphere and replacing it with new refrigerant
- Recycle means cleaning refrigerant on-site using recovery/recycling equipment without full ARI 700 testing (Correct answer)
- Recycle means sending refrigerant to a certified facility for chemical reprocessing
- Recycle means mixing different refrigerant types to create a new blend
Correct answer: Recycle means cleaning refrigerant on-site using recovery/recycling equipment without full ARI 700 testing
Recycling cleans refrigerant through oil separation, filtration, and moisture removal on-site but does not certify it to ARI 700 purity standards like reclamation does.
Question 5: A technician recovering R-410A notices the recovery cylinder is getting hot to the touch during the process. What is the MOST likely cause?
- The cylinder is overfilled beyond the 80% liquid level
- Non-condensables are mixing with the refrigerant during recovery
- The high heat of compression from the recovery machine is warming the cylinder (Correct answer)
- The cylinder is defective and must be replaced immediately
Correct answer: The high heat of compression from the recovery machine is warming the cylinder
Heat from the recovery machine's compression process transfers to the recovery cylinder as refrigerant vapor is compressed and condensed into it, causing it to warm.
Question 6: Which refrigerant requires special low-loss fittings on all service hoses and equipment to comply with EPA Section 608?
- All refrigerants covered under Section 608 (Correct answer)
- Only CFCs and HCFCs
- Only refrigerants with ODP greater than 0.5
- Only refrigerants used in systems over 50 tons
Correct answer: All refrigerants covered under Section 608
EPA Section 608 requires low-loss fittings on all hoses and equipment used to service any appliance containing refrigerants covered by the regulation.
Question 7: After completing refrigerant recovery, a technician must verify completeness by checking the system pressure. For equipment manufactured after November 15, 1993 with a charge between 50 and 200 lbs, what is the required final system pressure for high-pressure refrigerants?
- -23 inches Hg vacuum
- 0 psig
- 4 inches Hg vacuum
- 10 psig (Correct answer)
Correct answer: 10 psig
EPA regulations require a final recovery level of 10 psig for high-pressure appliances manufactured after November 15, 1993 containing 50-200 lbs of refrigerant.
CFC Refrigerant Handling & Recovery Procedures 5
What is the purpose of the 'liquid recovery' method versus 'vapor recovery' when recovering refrigerant?