The refrigeration oil looked strange!
I had never seen anything like it. A creamy yellow mess came rolling out of the refrigeration compressor crankcase.
Guess I should start from the beginning.
When I arrived on the job the packing house manager complained that his green beans were not cooling down.
Walking outside I quickly noticed one condensing unit off.
I found the compressor breaker tripped.
On high voltage equipment, I always check for electrical grounds before resetting breakers. High 480 volt equipment does scary things going to ground!
Nope, not grounded. The compressor ohmed out fine.
After attaching my refrigeration gauges, I reset the breaker.
At first all appeared normal. The compressor started up and both condenser fan motors were running.
Clipping my amp meter on a compressor motor lead made my eyebrows rise. Definitely not OK. The amperage was high and very unstable.
That's when I noticed the oil sight glass. I looked like something I had never seen before.
It was a mass of churning yellow paste. What the heck!!!
I turned my attention to the low side pressure gauge. It was reading lower than normal pressure.
But even stranger, the pressure was slowly dropping. Almost like something was restricting the refrigerant flow.
When in doubt, shut it off!!!
A little more information.
Green beans coming from the field must be cooled quickly. Because they pack so tightly in the box, a normal cooler doesn't work.
The air can't penetrate into the interior of the box.
What to do?
First cool the beans in water! A slow moving flue of cold water.
Now they're ready for the box.
In a green bean flue system the evaporator is submerged underwater. It works great, until there's a problem.
I thought I knew what had happened.
Water had been sucked into the evaporator.
I had a refrigerant leak on the evaporator. I also had a bad low pressure control.
Every time the condensing unit pumped-down, it pulled the low side pressure into a vacuum. This allowed water from the flue to be sucked into the evaporator.
This water mixed with the refrigerant and refrigeration oil. The result? A slushy ice mixture in the crankcase!!!
After finding and repairing the refrigerant leak, I replaced the defective low pressure control.
How did I get the water out of the system?
I changed the oil. Then changed it again and again and again... A total of 12 times.
While changing the oil, I also changed the drier cores again and again and again...
Eventually the sight glass moisture indicator indicated a dry system.
Refrigeration oil, refrigerant, and water all mixed together. It forms a cold, bubbling, oozing, yellow, creamy, mess!!!
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