Hi,
Can anyone think for expert solution on the following problem, kindly suggest if you have any idea in this.

Ambient Air cooled Liquid chiller
York model - YAEP99WD9C50PA
controller - YAEP
Compressor - York PC, 8cylinder, 2 unloader valves

Problem is with compressor loading
Compressor is running at 45% load continuously, not going in load.
Running parameters are
SP-75, DP-285, Oil pr-60, current-45%, temp setting 52-56, LWT - 68
checked- solenoid valves electric supply, not present (i assume there shouldn’t be for loading)
What could be the reason for continuous unload? i suspect any stuck up of unloader valves in side compressor but how is it possible for both at a time or any other reason could be?
Kindly suggest,
Thanks in advance
Regards
T.V.Rao