Quote Originally Posted by Peter_1 View Post
I also don't see a problem when pressurizing with air. Perhaps blow the air through a filterdrier, the one with a removable core and big absorbing area.
Vacuming removes the water very fast. In my evening classes, I demonstrate this with the small plastic container for a Danfoss orifice. This is anyhow a lot of water. I fill it up with water, place it in a glas container and vacuum it then. Al the water is vaporised within 2 to 3 minutes.
POE oil is hygroscopic substance. This is what I am worrying about. Have you checked it after blowing the system with air?