In a refrigeration system, oil separators are installed between the compressor and which component?

• A. Condenser and evaporator
• B. Compressor and condenser
• C. Evaporator and expansion valve
• D. Receiver and condenser

Answer: (B)

Oil separators remove entrained lubricating oil from the high‑pressure discharge gas coming straight from the compressor. Placing the separator in the discharge line just after the compressor and before the condenser catches most of that oil so it can be returned to the compressor crankcase, while the cleaned gas continues to the condenser. This keeps the condenser tubes from fouling with oil and helps maintain proper lubrication by returning oil to the compressor. Placing it elsewhere wouldn’t capture the oil at the right point in the cycle, so oil carryover to the condenser and other components would be more likely.