On which side should refrigerant be charged in an ammonia compression system?

In an ammonia compression system, refrigerant should be charged on the low side. The low side refers to the part of the system where the refrigerant is in a vapor state and at low pressure, typically found after the evaporator and before the compressor. Charging the refrigerant in this area allows for a more efficient and safe process, as it reduces the risk of over-pressurization that can occur if refrigerant is added to the high side, which operates under higher pressure.

Additionally, charging from the low side ensures that the refrigerant is properly mixed with the existing vapor in the system, allowing for better system performance and preventing potential damage to system components. Understanding the pressure dynamics within the refrigeration cycle is critical for effective operation, maintenance, and safety protocols in ammonia systems. This is why charging is specifically recommended to be done on the low side during normal operation.