Performance of R466A, a non-flammable replacement for R410A, in unitary air-conditioning and transport refrigeration.

Abstract

Use of R410A is under pressure to be phased down because of its high global warming potential (GWP). The recent Kigali amendment to the Montreal Protocol will necessitate the phase-out of R410A used in air conditioning systems in developed countries by the late 2020s. This will require the industry to begin using R410A replacements by the middle 2020s. A new refrigerant blend, R466A, has been developed with thermodynamic properties that potentially make it a design compatible replacement for R410A. This new blend offers a 65 % reduction in GWP over R410A and is non-flammable (Class A1). Tests of a blend with very similar composition in an air-cooled chiller and a residential split system heat pump were previously reported. Performance generally met expectations with capacity being slightly lower than R410A and efficiency being slightly lower than R410A in the chiller test and similar to positive in the heat pump test, all consistent with the thermodynamic properties of R466A relative R410A. This paper presents the results of tests run with R410A (as baseline) and R466A in another residential heat pump and a transport refrigeration unit. Again, performance is generally seen to meet expectations. Capacities ranged from -5 % to +2 % relative to the R410A baselines. Efficiencies ranged from -3 % to +4 % relative to the R410A baselines. These results demonstrate R466A's utility as a lower GWP, design compatible replacement for R410A in a range of HVAC&R equipment. Its classification as non-flammable permits R466A to be used in existing equipment designs, either in new product or as field replacement of reclaimed R410A.