POE oil is very hygroscopic and absorbs moisture like a sponge. POE will absorb 10 times more moisture then Mineral oil, which makes it much less forgiving. When POE oil has absorbed enough moisture it will break down into acid and alcohol that will attack system components. Once POE absorbs moisture and breaks down, filter driers and evacuation will not fix it.
The prevention of problems with POE is simple. Always start out with only clean and dry ACR pipe or line sets. Always install a filter drier and follow proper evacuation procedures which should incorporate a triple evacuation. The compound gauge on a service manifold is not accurate so a good micron gauge must be used. By using a micron gauge, pulling and holding a true 500-micron vacuum, a dry and leak free system is assured. This will eliminate costly callbacks and much larger more costly long-term system problems. If the old line set must be reused, or if the system encounters POE oil breakdown, RX-11 Flush is a great way to clean the system to prevent future problems. POE oil is a superior lubricant if handled properly. B-Y has refrigeration oils in stock.