WTF did you just say? Better leave that alcohol alone, ****'s burning the
cells faster than you're makin' 'em.





"DiDo" wrote in message
news:BMrNe.128$IG2.84@trndny01...
Gentlemen
I do not want blow you bobble however I think
that you are depending far to much on micron gauge
am I? nut no I am not I have been doing refrigeration work
guess? for over 40 years and field work since 1969
first good mechanic must visualized ( presume lost of gas)
how refrigerant was lost if is on high side or low side
if is on high side take in consideration what it will take to
fix the leak or problem and go from there on, it could
need just half hour or couple hours that determine how long
you will keep system open and to get it fix.
Low side leak again examined problem was the unit running
with no refrigerant in the system or did unit shut down on safety
how long was it with out any refrigerant in it, all this things
must be taken in consideration, only then you can
decide how long you will need to have it on vacuum
low side could be from hour to overnight and more if it
happen that solid water got into system, first you must
purge it with nitrogen (GN2) try to blow out all water as
possible then and only then put it on vacuum.
Now micron gauge With reading on the gauge
of 100 MICRONS YOU CAN STILL HAVE WATER
IN THE SYSTEM? impossible I have news for you
It is possible! how? well while water boils at low pressures
but it ALSO FREEZES and once it get frozen it does not
boils any more. Procedure is to pump system down
for couple hours then purge the system with GN2
let it sit for hour with GN2 in it then put on vacuum again
this procedure you may have to do few times depend
on size of the unit it self. I would also recommend changing
of oil "filter drier must" open and clean oil separator if there
is one plus add oil filter on return line On POE system
oil change is must and do not put clean oil in until
you have evacuated system first.
and no you are not boiling oil out what you see is oil bubbling
you are taken out residue of gas and moisture
Good luck Dido say that

"Travis Jordan" wrote in message
.. .
papaya wrote:
if you only pull 500 microns of vacuum for your customer, you are not
getting all of the water out and are going to be making hydrochloric
acid for them, so they can buy a new unit from you, Mr. Con Artist.

Most manufacturers installation instructions say evacuate to 350
microns, then insure that the vacuum holds for at least a minute after
closing off the vacuum pump. Their instructions (and their warranty)
are good enough for me.