Large low-pressure chillers
Traditionally, the market for large Chillers (about 500 - 1000 kW) prevailed R-11. R-11, which is considered to be such, operates at lower pressures than other refrigerants used in centrifugal compressors. With the phasing out of CFCs, some manufacturers have replaced R-11, R-123", which is HCFCs. Currently there are no suggested changing R-123 so these systems will likely need to be stored R-123, until they are decommissioned at the end of their life. Due to technical developments less suitable for this refrigerant, as well as concerns about the toxicity and reluctance to introduce transitional HCFCs product, most manufacturers have moved their production to R-134a chillers.
For large systems, screw and centrifugal compressors is typically used. Because of low efficiency of many of the old coolers and lack of opportunities for direct replacement, modernization of this type chillers, they are more often replaced with new refrigerants: a state-of-the-art chiller system often uses 30% less energy than the old chiller installation, which often result in the short payback period of additional investment to replace instead of modernization of the old block (Gartland, Lisa Positive Energy).
..
|
Refrigerants