For medium and small chillers
In the segment of low-power, Chillers traditionally used R-22 or R-12, non-ODS chillers were available during the last 15 years, whereas R-22 chillers were still being introduced in some markets. Basic alternatives R-134a, R-407C and to some extent, R-410A. R-134a is the most common in hardware higher cooling capacity and is often used with screw or centrifugal Chillers, where a larger volume flow rate required does not affect the cost, and, as with reciprocating compressors. R-134a also has the advantage that it is suitable for use in flooded evaporators that is not the case with R-407C, which has a significant temperature glide.
This temperature glide is not a serious technical difficulties in use in counter-flow heat exchangers with dry expansion, i.e.
plate heat exchangers, as well as in many air heat exchangers, which are not intended to be reversible. In systems that are intended for use as air conditioners and heat pumps, the challenge to use glide refrigerants becomes much more significant and R-134a or R-410A, becomes a more attractive alternative. The problem with R-410A is significantly higher pressure which may not be a problem for small split system air conditioning, but requires considerable reconstruction of the vessels working under pressure.
Design of the rooms is chillers HCFC proven, not only in industrialized countries but also in most Article 5 countries, where typically installed in several years, in parallel with the old system based on R-22 technology. The price difference is small and HFC technology often designed with today's energy efficiency requirements taken into account. New design of equipment with higher energy efficiency has also introduced techniques to minimize leakage and less charge.
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Refrigerants