I am the third tech put on this chiller 30GT 130. Problem is that Circuit B shuts off on High Superheat, then sometimes Low Superheat, and occasionally low oil. All sensors are good. Their are two new compressors on Circuit B, New EXV, new chiller barrell. It seems as if the EXV does the opposite that it should. The previous tech told me that the EXV wire colors changed on the new EXV (brown and white??). Going back on Tuesday to run through the Carrier EXV troubleshooting guide. Any further suggestions. I am the junior guy in our shop, would like to find the solution to his growing headache.