Diagnosable Remotely: YES
Fixable Remotely: YES*
*possibly
Symptom:
Plunger will not retract or extend in jog mode
Cause:
The plunger seal has become deformed. This can happen if there is air in the pump head when the machine does a pressure stroke. The air can be compressed and this can lead to cavitation in the pump head which can damage the seal, or it could allow some process fluids to combust and damage the seal.
This causes the seal to fold or roll into a position where it jams the plunger into its channel in the pump head. In jog mode there is not enough power supplied by hydraulics to overcome the friction from the jammed seal.
Solution:
The plunger seal must be replaced.
If the plunger is extended far enough for the customer to remove the pump head and do the seal replacement themselves, then this can resolved with remote support.
If the plunger is stuck at the top, then the customer may be able to force the plunger to extend by using run mode to extend the plunger under pressure.
If they are unable to replace the seal themselves then a callout will be required.