SD-95-12-3 -- Performance Tests of R-22 and R-32/R-125/R-134a Mixture for Baseline Air Conditioning and Liquid Overfeeding Operations ✓ Most Recent

Much experimental and theoretical analysis of potential R22 replacements has been accomplished. However, published information regarding the experimental analysis of any off-the-shelf air conditioners with a potential R22 replacement at realistic operating conditions is still rare. This type of work could be useful because it would provide baseline data for comparing the performance of R22 and its potential replacement at drop-in conditions. An off-the-shelf window air conditioner was tested at Air-Conditioning and Refrigeration Institute (ARI)-rated indoor conditions and at different ambient temperatures, including the ARI-rated outdoor condition, with R22 and with its potential replacement, a ternary mixture of R32 (30%)/R125(10%)/R134a(60%) (the ternary mixture). A test rig was built that provided for baseline operation and for the option of operating the system with a flooded evaporator by means of liquid overfeeding (LOF). The test results indicated that the cooling capacity of the ternary mixture was 7.7% less than that of R22 at 95degF ambient for baseline operation. The cooling capacity for both refrigerants improved when a flooded evaporator, or LOF, was used. For LOF operation, the cooling capacity of the ternary mixture was only 1.1% less than that of R22. The ternary mixture had slightly higher compressor discharge pressure, a lower compressor discharge temperature, slightly lower compressor power consumption, and a higher compressor high/low pressure ratio.

KEYWORDS: year 1995, performance, testing, R22, R32, R125, R134a, refrigerants, mixtures, replacing, air conditioning, windows, unit air conditioners, ambient temperature, cooling, capacity