Posted by George Goble on October 23, 2000 at 16:49:21: via: or 128.211.159.12
In Reply to: Re: Cryo-chem Self Sealing refrigerants (long/boring) posted by John Pastorello on October 23, 2000 at 11:28:29:
John,
Did this bench reefer have a dryer on it? A dry-eye?
Was it known if system was wet or dry before starting?
By the oil being "turbid"? you mean like it had "flakes"
or stuff floating around in it? or just black?
Without being there, I can only guess that there must have
been lots of moisture in the system, and possibly no dryer...
It would have to been so high, like a few drops of liquid water
such that the dry-pak got all used up and didnt get all the
water or it wasnt left to run long enough to take out all the
water, so when the cryo-silane was added, it found free water/air
in the circulating oil and activated in the oil/freon liquid itself,
which would make "flakes" or pieces of "sludge" to form. These
flakes would surely plug the expansion valve in a few seconds...
I have seen systems (ice machines), with water logged (new
Alco dryers), where no sealing happened, but nothing bad happened
either... The dry pak had first cleared the circulating moisture
from the oil/freon, but was unable to take out all the "trapped"
water (200-300 drops) in the dryer... so the silane just activated
in the dryer.. Cutting the dryer open later showed "orange/yellow"
solid silane all over the desiccant, but not in the rest of the
system.
As I said earlier, system needs to be dry, with no water logged
dryer for it to work. There is no perfect solution.
--ghg