The technician must isolate a parallel compressor system in order to recover refrigerant.

• A. Series condenser
• B. Parallel compressor
• C. Receiver-drier
• D. High-side pump

Answer: (B)

When recovering refrigerant from a system with multiple compressors arranged in parallel, you need to isolate the entire bank of parallel compressors so the recovery unit can capture refrigerant from that portion without interference from the rest of the system. This is done by closing the service valves on the suction and discharge lines around the parallel compressor group, forming a contained section for recovery. The other components—the series condenser, the receiver-drier, and the high-side pump—do not provide this isolation, so they don’t serve the purpose of isolating the compressor bank.