Originally Posted by
HJ Controls
check discharge superheat or suction superheat depending on chiller. then load up chiller, and watch and see if exv maintains proper superheat.
just say your discharge superheat is low like 15 degrees and you exv position is at the bottom range. This would be a good sign that the exv is probably sticking. Keep it simple the exv should maintain proper superheat. If in doubt pull it apart and in service mode run it from 0-100 steps. You can also ohm the windings, feel the pulsation as it drives up and down.
Better yet get the service manual for the machine your working on and use the guide lines.
Hope this helps