Measuring the effect of refrigerant type on the starting characteristics of residential air conditioning compressor motors

This paper describes a project wherein the primary goal was to determine if refrigerant type affects the starting characteristics of a typical residential air conditioning compressor motor. It has been known for some time that during heavy summer loading conditions, air conditioning load can lead to voltage instability of a large power system following a disturbance that causes large quantities of air conditioning load to start simultaneously. With new environmental regulations taking effect, the older R22 refrigerant systems used in residential systems will be phased out and replaced by R410 systems. These new R410 systems operate at much higher refrigerant pressures, which could possibly cause increased starting time for the compressor motor and exacerbating the voltage stability problem caused by air conditioning load following a power system disturbance. Therefore, a test apparatus for measuring the electrical quantities, and system pressures, for both types of refrigerant systems was developed. The test apparatus was then used to test typical units of both refrigerant types to determine if the new R410 systems produced less favorable compressor motor starting characteristics as compared to existing R22 units.