What is the purpose of oil traps in vapor lines?

• A. Capture oil from vapor
• B. Remove moisture from refrigerant
• C. Increase line pressure
• D. Filter vapor

Answer: (A)

Oil management is about keeping lubrication where the compressor needs it while preventing oil from riding along with the refrigerant vapor. An oil trap in the vapor line is designed to separate oil droplets that are entrained in the high‑velocity vapor. By providing a slow-down or a collection area, the oil coalesces and drains back to the compressor’s sump, rather than continuing through the vapor line to the condenser or other components. This ensures the oil returns to the compressor for lubrication, helps avoid oil buildup in the line, and maintains proper lubrication and heat-transfer performance.

Moisture removal, increasing line pressure, and filtering vapor are handled by other components or functions in the system, not by the oil trap.