ACR Journal

CMYK / .ai CMYK / .ai CMYK / .ai acrjournal.uk 29 REFRIGERANT very easy to convert direct expansion (DX) R404A and R507 systems to either R448A or R449A with lots of very positive feedback from users and engineers that conversions have been quick and e ective, with both of these two refrigerant now accepted and in common use. Whilst the situation with R404A may be relatively clear, many of the other GWP >2500 refrigerants were used in much smaller quantities and some systems may be much harder to convert. Equally reclaimed product is less readily available, so conversion or replacement of systems may be much more important. DX R507 systems can be easily converted to R448A or R449A as can R422A systems but will need a POE oil. Neither option should need the expansion valve to be changed. R422D and R434A DX systems that previously ran on R22 could be converted to R438A with a GWP of 2265 or R453A with a GWP of 1765. It has also been possible to convert some R422D systems to R449A, if the system pressure rating will allow, but will need a POE oil and may need an expansion valve change. Additionally, R434A systems can also be topped up with RS90 (GWP of 2481) Large flooded evaporator systems are gradually being replaced as many of these are 20-30 years old and may not be possible to convert. As with all conversions it is advisable to fully explore the suitability and conversion guidelines from the suppliers for the equipment in question before embarking on conversions. This east London grocery store was converted to R449A Refrigerant reclamation process and quality All recovered product should be returned to the re-processor adhering to the hazardous waste regulation procedures along with correct documentation, with the site holding a waste licence to reprocess refrigerant. All recovered refrigerant returned for reprocessing is typically out of specification for moisture content, acidity and high boiling residue such as particulates. After initial analysis to confirm product identity it is re-processed by a combination of distillation, cleaning and drying processes back to AHRI 700 specification which is the same conformity as virgin product. This enables it to be placed on the market as reclaimed product and it will perform in exactly the same way as virgin product. The F-Gas legislation requires that all cylinders containing reclaimed or recycled product must be labelled as such, have a batch number and identify where it was re-processed to facilitate traceability. All F-Gas records that are kept by a user also need to record that reclaimed or recycled product was used and where it came from. Looking ahead With the 2020 bans now upon us and the next phase down step in 2021, it will be essential that enough R404A systems continue to be converted or replaced to keep a supply of reclaimed refrigerant for those systems that are harder to convert. For those systems replaced with new equipment it is essential that low GWP refrigerants are utilised. The knowledge and experience of refrigerant suppliers such as Climalife will continue to help the industry adapt to the di erent challenges that present themselves.