← All RSES Flashcard Decks

Refrigerant Management Flashcards

7 cards from real RSES practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 Refrigerant Management flashcards as text
  1. What is the minimum required vacuum level (in microns) that most equipment manufacturers specify before charging a system with refrigerant?

    Answer: 500 microns

    Most manufacturers require evacuation to 500 microns or lower to ensure adequate moisture removal and verify system integrity before charging.

  2. A certified technician may purchase refrigerants in containers larger than 2 lbs without restriction under Section 608. What document proves this certification?

    Answer: EPA Section 608 technician certification card

    EPA Section 608 requires technicians to hold a valid certification card issued by an EPA-approved certifying organization to purchase refrigerants in containers over 2 lbs.

  3. During refrigerant recovery, the vapor recovery method is generally slower than liquid recovery. In which situation is vapor-only recovery typically used?

    Answer: Small systems or when liquid access is not available

    Vapor recovery is typically used on small systems or when the service valve configuration doesn't allow direct liquid removal from the system.

  4. Refrigerant R-744 is the designation for which natural refrigerant that is being increasingly used in transcritical refrigeration systems?

    Answer: Carbon dioxide (CO₂)

    R-744 is carbon dioxide (CO₂), which has a GWP of 1 and is used in transcritical refrigeration systems particularly in food retail and industrial applications.

  5. What action must a technician take if they discover a refrigerant leak rate exceeding the EPA threshold in an appliance with more than 50 lbs of refrigerant?

    Answer: Repair the leak within 30 days or develop a retrofit/retirement plan within 30 days

    EPA Section 608 requires that leaks exceeding threshold rates in large appliances be repaired within 30 days of discovery, or a retrofit/retirement plan must be developed within 30 days.

  6. Which of the following refrigerants has an ASHRAE safety classification of A2L, indicating it is mildly flammable?

    Answer: R-32

    R-32 is classified A2L by ASHRAE, meaning it has low toxicity (A) and is mildly flammable with a low burning velocity (2L).

  7. What is the purpose of performing a standing vacuum test after evacuating a refrigeration system?

    Answer: To check for system leaks and verify the vacuum holds before charging

    A standing vacuum test involves isolating the system after evacuation and monitoring the micron gauge; a rising vacuum level indicates a leak or residual moisture.