Following DuPont’s announcement last week that its refrigerants R449A and R513A were to be included in Bitzer’s latest selection software, the German compressor manufacturer has now confirmed that these as well as Honeywell’s R448A and R450A have also been included.
Bitzer has been offering a selection of compressors with this latest generation of HFC/HFO blend refrigerants since the beginning of this year – making them the world’s first compressor manufacturer to approve and authorise these gases.
Bitzer’s new selection software update (6.4.3) enables the design of systems using Ecoline compressors with R448A, R449A, R450A or R513A, and HSK/HSN-series semi-hermetic screw compressors with R448A and R449A.
HFO/HFC blends R448A and R449A have been developed as substitutes for the soon to be phased out high GWP commercial refrigeration gases R404A and R507A. The substitutes have about a third of the global warming potential of R404A/R507A.
Bitzer advises that when using R448A and R449A in existing systems with Ecoline or HSK/HSN compressors, the temperature glide of 5 to 6K must be considered as this has an impact on performance. In medium temperature applications their volumetric cooling capacity is said to be similar to R404A and R507A but in low temperature applications, it is somewhat lower. For an accurate comparison the software will provide usable and unusable superheat and liquid subcooling information for actual operating conditions.
Honeywell’s R450A (N13) and DuPont’s R513A (XP10) can be used in Ecoline compressors as a low GWP alternative to R134a.
R513A is an azeotrope, R450A an zeotrope, but with a very low temperature glide of 0.4K. Bitzer says that this means that both refrigerant blends can be treated as R134a. In medium temperature applications the volumetric cooling capacity of R513A is slightly higher than that of R134a and R450A is slightly lower. The discharge temperature of the new gases substitutes at medium temperature is about 6 to 7K below that of R134a, says Bitzer.
POE oil must be used and Bitzer recommends testing the acidity of the oil after six months.
The four substitutes are all classed as A1, non-flammable gases.
Selection software 6.4.3 is now available for download from the Bitzer website and as an online version at www.bitzer-software.com.
Lower GWP blends in Bitzer compressors – February 22, 2015
GERMANY: Bitzer has produced an information sheet for those considering using some of the new lower GWP refrigerants and blends with its compressors. Read more…