R32, HFO, A2L, GWP, LCCP, drop in, discharge temperature
This paper will review the status worldwide on technical and policy search for next-generation refrigerants with both low Global Warming Potential (LGWP) and low Life Cycle Climate Performance (LCCP) with particular focus on R410A replacement for unitary A/C & H/P. R32 and the HFO blends offer potential solutions but all involve tradeoffs among Global Warming Potential (GWP), efficiency, safety, and cost. With the U.S. mandating new higher regional efficiency standard taking effect January 2015, there is even more pressure in finding a Low-GWP refrigerant solution that is affordable and can sustain efficiency and reduce charge requirement. This paper focuses more on R32 as the available data for HFO blends is limited. Theoretical analyses and test results from various drop-in system tests with different heat exchangers and scroll compressors will be presented comparing R32 and HFO blends versus R410A. LCCP, system economics, compressor discharge temperature envelopes for typical US applications, as well as A2L flammability safety aspects will be discussed relative to the HFOs.