by Richard Kollmann » Sat Nov 28, 2009 5:00 pm
Vertical lines require twice the refrigerant velocity of horizontal lines to wash oil droplets off tubing into refrigerant flow. The normal Danfoss BD line from compressor to condenser is 3/16 OD. Condensers are designed so that refrigerant vapors and oil enter at the top and super cooled liquid refrigerant mixed with small amounts of oil assisted by gravity exit out lower part of condenser. The critical line sizes for refrigerant velocity will be after the refrigerant flow control device as Ester oil is not as mixable with refrigerant when in the gas phase state.