Conference Year



Low GWP, Systems, Case Study


The objective of this case study is three-fold: (1) identify promising alternative refrigerants with lower global warming potential (GWP); (2) among those, select refrigerant(s) that could be “drop-in” replacements for R-410A and would not require significant system redesign or compressor changes — with the exception of minimal changes such as lubricating fluid and expansion valves; (3) evaluate the impact of another easy-to-implement option: replacing lower-efficiency, permanently split capacitor (PSC) condenser fans and evaporator blower motors with electronically commutated motors (ECM) for additional system efficiency improvements. This study leverages the steady-state heat pump design model (HPDM) developed by the Department of Energy (DOE) and the Oak Ridge National Laboratory (ORNL) to demonstrate three key findings: (1) two popular refrigerant replacement candidates with a GWP less than 750, R-32 and R-454B; both have system performance equal to or better than R-410A; (2) the lower-GWP refrigerant options with a GWP below 300 all underperform compared to R-410A; however, heat exchanger optimization may improve system performance; (3) using an ECM instead of a PSC evaporator blower motor increased system seasonal energy efficiency ratio (SEER) performance ~8% for all refrigerants evaluated.