What is the role of the condenser in an ammonia system?

• A. To absorb heat and vaporize the refrigerant
• B. To regulate refrigerant flow to the evaporator
• C. To reject heat and condense the refrigerant from vapor to liquid
• D. To compress the refrigerant

Answer: (C)

The condenser in an ammonia system rejects heat to the surroundings and condenses the refrigerant from a vapor into a liquid. After the compressor raises the ammonia to high pressure and temperature, it exits as a hot vapor. The condenser removes that heat so the vapor cools and changes phase, forming a high-pressure liquid (often subcooling a bit for stability). This liquid then moves on to the expansion device and into the evaporator, where it absorbs heat and vaporizes to continue the cycle. If heat rejection didn’t happen, condensation wouldn’t occur and the cycle couldn’t proceed. Absorbing heat and vaporizing occurs in the evaporator, not the condenser; regulating refrigerant flow is handled by the expansion device; and compression is performed by the compressor, not the condenser.