EPA Section 608 Universal Certification ExamType I (Small Appliances)Easy
A technician is performing a recovery on a small appliance with a non-operating compressor. To maximize the recovery of refrigerant using a system-dependent (passive) recovery device, what action should the technician take?
- AHeat the compressor and cool the recovery cylinder.
- BCool the compressor and heat the recovery cylinder.
- CCool both the compressor and the recovery cylinder.
- DHeat both the compressor and the recovery cylinder.
Show answer & explanationAnswer & explanation
Correct answer: A. Heat the compressor and cool the recovery cylinder.
System-dependent recovery relies on pressure differential. Heating the appliance (compressor) increases its internal pressure, while cooling the recovery cylinder lowers its internal pressure, creating a greater pressure differential that drives refrigerant into the cylinder.
Why the other options are wrong
- B. Cooling the compressor would lower the appliance's pressure, and heating the recovery cylinder would increase its pressure, which would reduce or reverse the pressure differential, hindering recovery.
- C. Cooling both components would lower pressures in both, but wouldn't create the necessary differential to efficiently transfer refrigerant into the recovery cylinder.
- D. Heating both components would raise pressures in both, potentially reducing the differential or making it harder to move refrigerant into the cylinder.
Maximizing Passive Recovery (Non-Operating Compressor)
To maximize refrigerant recovery from a small appliance with a non-operating compressor using a passive device, heat the appliance (e.g., compressor) and cool the recovery cylinder to create a larger pressure differential.
- Applies to passive (system-dependent) recovery.
- Requires a pressure differential for refrigerant transfer.
- Heating the appliance increases its pressure.
- Cooling the recovery cylinder decreases its pressure.
Memory trick: Hot appliance pushes, cold tank pulls.