Hi all,
I have a relatively new Hansen HA4AS-100 on an evaporator wet suction return acting as a defrost pressure regulator and evaporator pressure regulator. NH3, 65KpA suction, 400KpA pumped LP liquid, -10degC room temp. The evaporator pressure is regulated by a Danfoss CVQ installed on a pilot line and a EKC is used for control of air on temp.

What I'm experiencing is the Hansen valve will not open fully in normal operation. With the Hansen valve jacked open the evaporators perform as expected, once un-jacked the performance reduces, brining of the coil is witnessed, the evaporator pressure rises to near room temperature equivalent. The CVQ is at min temp/fully open

What I have noticed is the pilot line is connected upstream of the valve/strainer. This line is taken off the top of the 100NB pipe yet has ice/liquid in it during normal operation and disappears when the suction valve is jacked.

Is liquid on top of the suction valve piston ok for normal operation? Maybe the HEV are too far open?