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Oil Seperators

Techman Member Posts: 2,144
Outta what comes outta a comp discharge line, how much oil goes down the discharge line as compared to how much oil goes back to the compressor thru an Oil Seperator? ? I'm trying to figure out how soon two 15hp comps will die. This is on a brand new system, so I'm trying to figure out how much of the oil will go down the discharge line to the remote air cooled cond coil and not return, in "per hr" amounts I guess. I am just a casual observer here, I am not involved in any way,shape ,or form.


  • pecmsg
    pecmsg Member Posts: 3,570
    Every system is different as are the piping practices so it's difficult to say.
    At one of the Copeland / Tecumseh classes I remember being told “guestimate 90% of the oil going to the separator will be trapped and returned to the sump. The other 10% will be taking the long road back.”
  • Techman
    Techman Member Posts: 2,144
    Thanks Paul , thats a start.
  • Techman
    Techman Member Posts: 2,144
    edited October 2014
    This is what I found out. On a 15t system w/ a 15* evap temp,110* cond temp the amount of freon pumped by the comp is about 1,790 lbs/hr, the comp typically pumps oil at 1% ,so, 17.9 lbs of oil per hr goes into the seperator,so, that means the conventional oil seperator returns 90% of the oil back to the comp crankcase and pumps 10% (1.79) lbs/hr out into the discharge line.