problem with volume on frick screw compressor

[samlee12]

Having trouble with Frick screw mod# RWF 11 222 E. At 0 percent load i have a volume of 5 but when the screw starts to load up my volume starts to drop to min. Vi of 2.2.When the compressor reaches 100 percent i get a message saying unload, increase volume on the micro it is showing that it is giving signal to increase but the Vi will only go to 2.88 Vi.Checked the wiring checked the solenoid every thing in normal but Vi will not increase. When the compressor is unloading my Vi will increase as my capacity decreases.Called Frick to ask them there input into the situation he asked me to give him the voltage readings for the slide vavle and slide stop valve. My voltages for capacity fully unloaded min. position i have voltage fo 3.8 v on the loaded max position voltage is 4.65, for the slide stop voltage at min. is 3.26 and at max is 4.53. Frick told me the voltage read by slide stop seems to be fine but capacity voltage seems out of whack. Told me the slide valve sensor probably faulty and causing me to have trouble with volume. I don't see how the capacity sensor or slide valve position can affect my volume was wondering if anybody has come across this problem.Sorry seems i posted this question in two places one in industrial and one in industrial compressors.