Hunting Down the Source of Water Contamination
An MRT client accustomed to monthly oil sampling tracked three straight months of water contamination of ~500 ppm in a compressor lube oil system. Seemingly nothing about the system had changed and the compressor had been fully operational. Samples were pulled consistently from a sampling valve on the system discharge return to the reservoir. Spectroscopy detected sodium and potassium in the oil samples and the oil was noticeably hazy in appearance. Because of the contaminant elements that appeared in conjunction with the sudden water contamination the most likely scenario was a cooling water leak into the lube system. But there were no traces of leaching copper from a hole in the tubing and more importantly this system didn’t even have an oil cooling system.
There was no logical reason that cooling water would be contaminating the lube oil. The client decided to pull a sample from the reservoir drain in hope of gathering free water to analyze separately from the lube oil. He was successful, the water had a green hue and the conductivity of that water was >700 mmho/cm. Cooling water was definitively in the system, but how did it get there? They suspected fill port contamination and subsequently asked the lubrication technician to walk through the process of adding lubricant to that system. The lube tech was using the same bucket for pouring in glycol and lubricant to their respective application points. Self-inflicted cross-contamination was the cause.