McQuay WSC087 Electronic Expansion valve control

This is a McQuay Centrifugal with EXV, I am not able to get this to be stable, have to visit the site almost everyday and do those Gain and slope settings. As per McQuay the algorithm looks at lift, Condenser or Chilled water Delta T, adjust the gain/slope to control the EXV, but after the chiller is re-started it is either taking in liquid or causing low evap pressure. :confused:

At one point I loaded the chiller to 100%, set it to maintain correct superheat and disconnected the EXV. Worked good for a week until I put it reconnected it.

:confused::confused::confused: