Drop-in Testing of Next-Generation R134a Alternates in a Commercial Bottle Cooler/Freezer

Next-generation refrigerants with lower Global Warming Potentials than traditional HFC’s are being commercially introduced. Drop-in performance tests were conducted in a commercial bottle cooler/freezer. Tests were conducted with R134a as a baseline and several next-generation refrigerants and blends. The tests were conducted in accordance with ASHRAE Standard 72 at -5.6°C and 3.3°C bottle cooler temperature setpoints. Two ambient conditions were tested, 23.9°C/55% relative humidity and 26.7°C/55% relative humidity. In addition to the ASHRAE test conditions, full pull-down and half pull-down tests were conducted in accordance with a soft-drink bottler’s specifications. Performance parameters such as discharge air temperatures, product simulator temperatures, suction pressure, discharge pressure, compressor mass flow rate, and compressor input power were measured and compared. With the exception of HFO1234ze(E), all the substitute refrigerants had similar performance as R134a. HFO1234ze(E) had lower density at compressor suction conditions and therefore resulted in longer compressor run times and longer pull-down times. A larger displacement compressor would likely bring HFO1234ze(E) to roughly the same performance as the other refrigerants