oil plate leaking?

im working on a lyophilizer (freezedrier) and i noticed the other day, that that on the bottom plate for the compressor (this is a copeland semi-hermetic) there where drips of oil coming from all the bolts that hold the plate. i tightened the bolts best i could, wiped the plate as clean as i could, and continued my atempt at pulling a good vacum on the system. I know some oil seepage is normal, but the next day the oil was there again.

this unit has been worked on by quit a few incompitance, i know this. There are several cans of synthetic refer oil sitting next to this machine. could it be the synthetic stuff is to viscos?

Another thing is im pulling a vacum how would oil get out, if anything wouldnt it suck air in? Maybe its residual oil?

most of the systems i work on are hermetic compressors so im a bit inexpierienced.

Very interesting.

I have seen Copeland semi's do this also, and have been able to tighten the bolts (and they be noticeably "loose"). Sounds like you should pull the compressor and replace the gaskets. You can get a gasket kit from your wholesaler.

The crankcase is isolated from the refrigerant circuit via a check valve. This is in order to prevent oil from being pushed out of the crankcase into the suction. Is it possible that while you are pulling a vacuum, the crankcase is isolated in such a manner that it may still be under some pressure?

:)

i must say thats even more interesting. matter of fact it hurts my brain to imagine. im aware of this valve and am very impressed. However the king valves are bad, like i thought theyd be,. So there on order and now i gotta wait and see.

good job man thats a doosy

I couldn't find exactly what I'm looking for. The diagram of the semi-hermietic crankcase exists in the Copeland refrigeration manuals, which pictorially isllustrates the arrangement.

But I found this link, which notes the condition of "positive" crankcase pressure. I thought you might find it intresting.


http://www.copeland-corp.com/co/co_6_3_.htm#Q14


:)

It just so happens, i atended a class put on by copeland (free Food:) :) jk) and they did an excellent job. They explained all of the compnents of their compressors with a very good slide show. They even had the crazy old copland guy look at some compressors that had been brought in for core, and he could tell us exactly what was wrong (what the technician had done wrong)
just by the rust or the dust stains. When we opened them up, his diagnosis of all three was corect. One lugged real bad (over charge or no load). one over heated. Anyway it was incredible. Its really good to know people like that crazy compressor guy are out there:) . Well what i was gettin at is they gave me an excellent hand out, and i will try to scan it on monday so i can post it. only 4 pages but its goood stuff. THanks again man