HFO-1234yf, refrigerant, low-GWP, stationary
In recent years, HFO-1234yf has been introduced as a low global warming potential (GWP) replacement for HFC-134a in a variety of refrigeration and air conditioning applications both as a pure fluid (mildly flammable) and in refrigerant blends (both mildly flammable and non-flammable). A large and growing body of work on HFO-1234yf exists for mobile air conditioning, however recently interest in the use of R-1234yf in stationary refrigeration applications is growing. This paper will report the results of the longest continuous test to date (> 4 years) of a commercial stationary system operating on R-1234yf refrigerant. The test was initiated in 2009 in a 4ft reach in chest freezer by recovering the R-134a and replacing with R-1234yf. Since that time the system has operated normally and energy usage and operating data has been continuously collected. Recently, the freezer was shut down, refrigerant and oil samples collected for chemical and physical analyses and the compressor removed for a tear down inspection. Operational and energy performance data for the system over the duration of the extended test period will be presented and compared to baseline operation on R-134a. Results of the system performance data as well as the chemical stability measurements of R-1234yf and POE oil, along with the compressor tear down metrology will be used to validate the long term viability of this new class of low GWP refrigerants (HFO’s) and R-1234yf in particular.