Haveing a problem with York chiller. It was oragnialy design for chilled water only. But York said it would be ok to run with glycol with low temps glycol. There is 1 W compesser and 1-Vcompressed system runs on R22normal opertion is suction pressure23# on one comprsser the other for some reason operates at 10psi suction. One comp is operating at suction 10# and trips on low suction the other 23# and works ok. THE expension valve has been changed 2x. And all seems ok for a while then sunction drops on one compresser drops I notice that expension is frosted. There is also a solnoid on the high side after the king valve for load sheadding. Could it be that its passing by causeing low suction?