better utilization of the evaporator, creating an increase in pressure and a reduction in superheat temperature entering the compressor. Higher pressure vapor entering the compressor is possible with LPA leading to an increase in compressor capacity, thus providing further efficiency gains.  It is thought that the potential reduction of super-heated refrigerant vapor temperatures via LPA reduces the expansion of reciprocating compressor cylinder walls and therefore improves reliability. 

Moreover, lower Compressor Discharge Pressures can then offset this elevation of the Liquid Line Pressure. Improvements in Refrigeration System Efficiency of up to 50% are achievable according to operating conditions.   Annual improvements of 20%-40% are more normal due to the limits on savings during the warmer months. 

It is well documented that reduced Compressor Discharge Pressures and the corresponding reduction of compression ratios in a refrigeration cycle are desirable in that reduced energy consumption and increased system life are the result. These provide reduced operating costs and increased equipment life cycle. However, a problem then arises in that as Compressor Discharge Pressure is decreased, flash vapor (the partial re-evaporation of liquid refrigerant which has been condensed) in the system liquid line (and receiver if fitted) increases.  Any occurrence of Flash Vapor in a refrigeration or air conditioning system will result in a direct loss of refrigeration capacity within the Evaporator.  The resulting increase in running time alone to meet the refrigeration load will lead to increased energy consumption and the refrigeration system therefore becomes less efficient.