Have anybody worked with these chillers? We are servicing around 10 of these that our customer has.

These units has water chilled condenser, shell and tube, when recovering the refrigerant (90 KG r134a) per circuit there is no valve on the bottom of the receiver/condenser and we have to recover everything via vapor phase, it can take several days just to recover one circuit, is there any other solution to doing this? (other than soldering in a service valve after the unit is recovered)

And also when changing filter dryer, there is one stop valve at the outlet of the receiver/condenser just before the filter housing, nothing after the filter housing, just the electronic expansion valve. Are we suggested to trust the EEV to be closed?