Alternative refrigerants for air conditioning systems


To support the market transition, Danfoss qualifies its product ranges for the use with lower GWP refrigerants

Depending on the system capacity, the dominant refrigerants are R134a, or R410A. For air-conditioning applications where Danfoss has the widest portfolio for superior part load efficiency – ranging from 3 to 350 TR, is testing its compressor ranges with the following alternative refrigerants:

  • Danfoss fixed-speed scrolls: the new, R410A based, DSH scroll compressors with IDVs, that will be released in 2016, are being tested with the high density R454B (DR5A), DR55, R32 as alternatives to R410A. Currently, the DR5x-blends shows the best characteristics to pursue a drop-in strategy that minimizes the transition effort and product complexity from either a compressor or a system standpoint, both of which are showing good performances in preliminary results for what efficiency, capacity, operating envelope and oil compatibility aspects are concerned. These alternatives have global warming potentials (GWPs) ranging from 490 to 676, representing a 68 to 78 percent reduction compared to R410A and are in line with the European estimated GWP average value by 2030.
  • Danfoss inverter scrolls: the inverter scrolls VZH will be made available to operate with the same alternatives as Danfoss scrolls with IDVs.
  • Danfoss Turbocor® compressors: in 2013, the company launched the Danfoss Turbocor® TG310, the first centrifugal compressor that operates with the ultra-low GWP refrigerant HFO-1234ze. The TG310 compressor has a 3% higher efficiency than the equivalent Danfoss Turbocor® compressor using HFC-134a. In 2016, Danfoss plans to expand the TG product range for ultra-low GWP from 60Tons (220kW) to 145Tons (500kW) of cooling capacity. This expansion will not only include high efficiency products to operate with the ultra-low GWP HFO-1234ze, but also other low-GWP refrigerant blends.

Illustration 1

COP comparison; the numbers in the map represent the advantage (in %) of the COP of a compressor operating with DR55 vs. a similar one operating with R410A

Illustration 2

The Discharge Gas Temperature of scroll compressor using R32 illustrates the challenges of applying R32 as a drop-in solution