i have changed both items on Trane,York R-22 screws whats up with Carrier....POS.seems to be a major project to do either on this 23XL we are on ...have to iransfer the freon away from the oil receiver to get the oil out..told you will blow a good part of the charge out of the unit just to get that oil out..the filter is on the horizontal with a relief on top of the cannister cylinder will it hold the charge along with the shutoffs to isolate the freon.........thanks