EPA Section 608 Universal Certification ExamType II (High-Pressure Appliances)Medium
A technician is using a system-dependent (passive) recovery device to recover R-22 from a small high-pressure appliance. Which of the following is a key limitation of system-dependent recovery that might affect its efficiency?
- AIt typically recovers refrigerant at a very fast rate.
- BIt is suitable only for low-pressure refrigerants.
- CIt requires an external power source.
- DIt cannot recover refrigerant when the system pressure is low.
Show answer & explanationAnswer & explanation
Correct answer: D. It cannot recover refrigerant when the system pressure is low.
System-dependent recovery relies on the pressure differential between the appliance and the recovery cylinder. If the system pressure is too low, or if a significant amount of refrigerant has already leaked, the device may not be able to recover effectively.
Why the other options are wrong
- A. System-dependent recovery is generally slower than self-contained (active) recovery, especially as system pressure drops.
- B. System-dependent recovery can be used for high-pressure refrigerants, provided there is sufficient system pressure.
- C. System-dependent recovery devices do not require an external power source, which is an advantage, not a limitation.
System-Dependent Recovery Limitations
System-dependent (passive) recovery devices rely on the appliance's internal pressure and ambient conditions, making them subject to certain limitations.
- Relies on system pressure; inefficient if system pressure is low.
- Cannot pull a deep vacuum.
- Recovery rate can be slow, especially for vapor.
- Does not require external power, which is an advantage, not a limitation.
Memory trick: Passive is SLOW, LOW pressure is a NO-GO.