How are the motor windings on this machine cooled? Via refrigerant? If so I'd be looking at the low charge perhaps contributing to the problem. Any record of discharge superheat taken?
Surging is murder on a chiller comp and motor. What were the causes behind low chilled water flow?
Building Physics Rule #1: Hot flows to cold.
Building Physics Rule #2: Higher air pressure moves toward lower air pressure
Building Physics Rule #3: Higher moisture concentration moves toward lower moisture concentration.