Where does the oil go

[johndief]

Have Hussman rack with 2 22Hp compressors, and hot gas defrost, for the last 2 years we have had to add 3 gal of oil to the unit only to take it back out in summer. We have checked the split condenser pump out a couple time and seems to work. Any thoughts on other places to look for the oil getting hung up.

[dangpgt97]

I think your answer lies in the fact you have to add oil in winter and take it back out in summer.

[johndief]

I agree, but other than the split condenser I cannot think of anywhere that would be large enough to hold all that oil that is not in the system all year long.

[dangpgt97]

I wouldn't necessarily try and think of a specific area the oil is gettting trapped. If your system is piped correctly and the head pressure isn't falling too low in the winter the oil should be coming back. Seeing that it only happens in the winter I would look at the head pressure setup. If all that checks out then your gonig to have to dig deeper.

[thefreezerguy]

I think your answer lies in the fact you have to add oil in winter and take it back out in summer.

Agreed. I would look to see if the split valve is leaking by. I have seen it numerous times. Thje oil can log in the discharge line of the summer winter side of the split valve.
Before adding oil next time, run the condenser in full and see what happens.