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ammassi
14-09-2009, 05:14 PM
Hi everybody,
this is my first post on this forum so I apologize for any mistake I will do (if any).
I have to develop a logic to control the refrigerant level (R134A) on a flooded evaporator unit probably using an electronic valve. The main purpose should be to avoid oil unbalance (two screw compressors on one circuit unit) and maximize performances.
What I saw in my short experience with this kind of evaporator is that an unbalance in compressors capacities could create rapidly oil migration between separators. At the same time if the compressor injests liquid the oil start to circulate and in the evaporator will be possible to see foam formation. If this happen to only one circuit the oil migrate to the other compressor.
Now this is the result of observations with a weak methodology.
My question is, how can I keep the refrigerant level to have the maximum performance in terms of heat exchange and at the same time avoid to loose oil (this should increase the isoentropic performance)?

Thanks.

Kind regards
AmMassi