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Add POE oil by weight or measure

Changing oil in Coplamatic compressor from MO/POE mix to POE. New compressor came charged with 80 OZ Ester. When running oil level was just at top of oil sight glass. I assumed MO returning raised this. I removed 67 Ounces by scale weight, by measuring cup it was 66 oz. That was all the oil I could suck out of the CC with hand suction pump. No drain plug on this LALA-310.

I put in 60 oz by measure cup. Sight glass at 3/4 level now. Plan to change two more times to try to get more MO out by dilution. Then recharge system from R-12 sub of R-414B to R-134A. (about 1/5 the cost).

So is the measuring cup and scale weight the same amount of oil, it seems the same to me. Thanks

Comments

  • Jamie Hall
    Jamie Hall Member Posts: 16,329
    Very close. The measuring cup is measuring volume, the scale is measuring actual weight. The measuring cup is calibrated to water, which has a specific gravity of 1.0. The oil is, perhaps, slightly more dense -- I'd have to look it up.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • Techman
    Techman Member Posts: 2,144
    edited November 2015
    You had me thinking there for awhile, until Jamie came along!!!!! At my last Copeland 3 day Class (spring 2015)we were told that the % of "oil to oil" ratio has been changed from the "old rule" of 95% new oil vs. 5% old oil to the "new rule" of "more than 51% new oil to less than 49% old oil". Good Q!!
  • JUGHNE
    JUGHNE Member Posts: 8,545
    By new oil to old I assume you mean the ratio of new POE to old MO. So one more change of oil should be more than adequate? 51new to 49 old. That is a big change of opinion over about 20 years.

    So this label of 80 oz; with oil just over the top of glass I could only get that 66 oz out of cc. So some of the new 80 oz is out in the piping? Being brain dead for a moment I failed to look at the oil level before first start up. If there was 80 oz in there it would have been well above the sight glass, it seems.

    One more dumb question; the 1/4" IPS oil fill plugs have a screw in the center with the little rubber tit on the other side.....the reason for that special plug is??????
  • Techman
    Techman Member Posts: 2,144
    edited November 2015
    Another new Copeland rule is that the oil has to be "within the oil glass". I think that the rubber plug is how they pressurize the comp w/dry air/nitrogen. A "needle" goes thru the plug, pressurizes, and the needle gets pulled out and the rubber "self seals".

    LOL, what do you mean by a dumb Q? So far, haven't seen that from you, in any of your threads. Now, me on the other hand, dumb is a nice word for some of my Q's over the decades. I've been told "Thats stupid, asinine, idioic,, very apprentice like, and a few even laughed. But I always ask anyways. I even ask Q's for other guys that "will not ask" ,cause they don't want to appear "stupid,assinine,etc".
  • JUGHNE
    JUGHNE Member Posts: 8,545
    Thanks, "Pete's Plug" but with cap screw I guess. I'll put a Schrader fitting there for final oil addition. I recall now having done that before to top off level.
  • Techman
    Techman Member Posts: 2,144
    You can add oil thru the SuctionServiceValve or into a SuctionFD. But knowing the CC press comes in handy once in awhile..
    You might want to see what the CC oil level is at the end of a normal run cycle. Some systems have oil return problems with piping, sizing,lo loads, etc, causing a oil level drop in the comp. Is there oil protection ?