500 microns? - then you are a HACK!!

Frozen water changes directly from the solid into the vapor phase under low pressure conditions, due to a phenomena known as 'sublimation'.....IOW, no "boiling" is needed.

What are these fabulous 'microns' you speak of, and where may I obtain them?

Are they expensive?

I must have some.

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.

You're a uninformed dipstick who posts about things you don't know s*it about. At 500 microns water boils at minus 12 degree's which is plenty to get the water out. At 50 microns you're boiling the oil out.

Well, I spose it was rather unrealistic of me to expect an illiterate f****it such as yourself to actually comprehend much if any of the information contained within the link I posted, and I guess I might be one of only a few that actually paid much attention in 9th grade science classes.

Still, appreciate if you don't send me anymore email on the topic.

Jake,

Doesn't matter--next time it snows, watch your outside temp real close, and take note of any period over several days, or perhaps up to a week where the temp stays constantly below freezing....notice that the snow 'just kinda dissapears'....given enough time, it will eventually dissapear altogether, without ever reaching a temp above freezing, and without rain falling on it, etc.....now note that this process speeds up considerably at pressures below atmospheric.

Dude, I got no idea what you are babbling on about. reply below

Maybe if your pump is too big...

Umm..... you better check the specs on *new* pumps... they are rated for and tested for a *maximum* of 50 microns

Do it right with N2 purge while brazing, new filter dryer, and use a small vacuum pump(4 - 6 CFM) with new oil, and you won't have a problem drawing down to between 300 - 400 microns. Too big of a vacuum pump will cause too fast of a draw-down and cause any water in the system to turn to ice. OTOH, If you are really gonna be that anal and have the time to leave your vacuum pump on a resi system for 2 days while trying to draw it down to 50 microns, then by all means, knock yourself out.

Frozen water changes directly from the solid into the vapor phase under low

keep on dreaming you will learn sooner or later From Dido

My dear freinds who ever told you that, he or she better get little more knowlage and experience or is it what you saying that if I evacuate system to

Dont be a f****it.

_Pressure_= heat.....

And so now pray tell just what the hell is this mysterious 'substance' youve added ( to the case in point)

Hmmm.......

Given a vacuum with some small amount of frozen water in it........will it ( eventually ) sublime or no ???

A single stage pump cannot pull a vacuum that can remove moisture.

Dildo YOU need to do some reading.

Cite your sources dildo. Or do you just pull s*it out of your ass like weasel does?

Answer one question on how many units did you work that do run at

-85 degrees Fahrenheit and must make -100 yes you can use R-11, R-114 and few others but field person must use what is readily available and don't come telling people what is in book but from your own experience work done. ANYTHING I POST I HAVE ALREADY DONE IT I do not IMAGINE IT I did it I suggest not only to you but to any that read this get some books on ultra low temperature and start reading before you come back to me with some stupid answers that you have no idea of what the heck you are talking about it is bloody disgrace that some of you. servicing air conditioners and nothing ales as long as you being doing this and you think you are expert on refrigeration, with answers and posting you gave if I was to gave you to clean my bathroom I strongly believe that my bathroom would be insulted, and Johnny this does not only pretend to you. You have big company

No, not without heat added.

No, not when the water is hydrating another substance.