Quote:
Originally Posted by TomWS
Let me see if I understand.
Even if I use compressed atmospheric air (not specially dried) to pressure test the lines, since there is so little volume in the linesets, I won't be introducing a total amount of H2O that is outside of specification?
Further, if I then vacuum the lines to 500 microns (or, at least, below the vapor pressure of water), then the bulk of even that limited amount of water will be removed from the linesets?
Tom
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Vacuuming the installation tubing below 500 microns will forgive you all sins you have done before it (air-pressure test).
Purging only by BBQ will leave acc. to calculation 0,2mg H20 inside the pipeline + H20 ,which is attached to the inside pores of the Cu tubing (impossible to now the quantity => heat treatment of the tubes prior installation undrer shieding gas would chase away the traces of H2O from pores).This is a DIY-man`s approach if vacuuming gadgets not available.A dryer in the circuit , however, is an exellent remedy for that.
Using vacuum you always know afterwards ,how much humidity left in the installation pipeline. You may have done exellent job in vacuuming ... but ...
there is a wet junk-yard called POE-oil in the system.You may only hope that the discharge line temperatures stay below acceptable levels (<+110degC).Otherwise overheated POE-oil turns partly into acid and water.
And then you have hell loose in the system.
If there is not "too much non-condensables" (or for ex.slurry blocking the streamer at MD) in the system , too high discharge line temperatures should not be a problem,I guess.I am not pretty familiar with this area ...
My point is that vacuuming is like shooting a mosquito by missile ... as a DIY-man I would think of other options as well!