Compared to Pumped Circulation System
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• Reduced charge with the low-pressure receiver (typically 70% less)             
• Reduced capital cost
• Simplicity of operation
• No power required for refrigerant pumps
• Easier to maintain
• Less pressure drop in wet suction line
• Smaller suction and liquid lines
• Simpler and more efficient defrost system
• Simpler control system

 
Compared to DX Systems
 

• Enhanced efficiency
• Lower compressor discharge temperature
• Better use of evaporator surface (flooded operation)
• Good distribution in evaporator due to sub-cooling
• Receiver can store excess refrigerant
• Higher reliability and reduced risk of compressor damage
• All control valves on the packaged unit
• Can combine easily with reversed cycle defrost
• Improved efficiency in low ambient conditions
• Longer life and lower maintenance costs
• Minimum sitework required
• Closer approach temperature in evaporator (no superheat)
• Automatic oil return from evaporator
• Performance not adversely affected by pressure drop in liquid line
• Better control under part load conditions

 
 Benefits of using low pressure receivers with ammonia.

• evaporator is overfed purely because the effect of the refrigerant has been increased by the sub-cooling.
• it acts as a liquid receiver.
• it acts as a suction trap.
• it allows refrigerant to be supplied to the evaporator, which can then operate in a flooded manner.
• it allows excess evaporators to be operated efficiently at very low temperature differences (no need to produce a superheat signal in the evaporator).

• it allows the ammonia expansion device to be of the high-pressure float type.

• it allows the collection of excess lubricating oil which can be returned to compressor suction. The evaporator is overfed purely because the effect of the refrigerant has been increased by the sub-cooling.
• It reduces power consumption
• Compressor/receiver packages built in factory so less site work