Those big skyscrapers sometimes use semihermetic compresssors (like boat
motors, or car engines). Which have a crankcase for the oil.

Refrigerators do mix the oil and refrigerant, and so for refrig, that's
normal.

As to mixing th eoil and refrigerant, that's a new one to me, I do mostly
small stuff, not skyscrapers.

As for the new fridge, I think the major problem is oil in the piston. Cause
oil isn't compressable. I've seen a couple cases where folks tipped a fridge
to move it. When they plugged it right back in, it killed the compressor.


--

Christopher A. Young
Learn more about Jesus
www.lds.org
www.mormons.com


"Peter H" wrote in message
...
I'm hoping someone in this group will take the time to answer this for me.

I'm in the middle of a course on HVAC in high-rises. The instructor has
stated that the oil in the HVAC system should be checked regularly for
quality and impurities. She says that if refrigerant is detected in the oil
then there is a problem. I was always thought that there is oil in the
system with the refrigerant and that this oil lubricated the compressor
etc.and one would expect to find refrigerant mixed in with it. I thought
that this was why you are always told to let a newly delivered fridge stand
for an hour or two before turning it on, to let the oil drain back down into
the compressor.

What gives?

tia

Peter H