[QUOTE=1eye82;13589631]We have all done changes under low pressure yes it works and we don't notice any difference in the operation. But you get a science geek in a lab with all their fancy instruments and they prove that moisture does get in to the system. You don't need to fully understand it but that is why we are techs not scientist.
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Techs are not the only people on these forums. There are also engineers and an occasional scientist and many smart people. Because of that you might want to be a little careful stating that there is in fact scientific tests proving what you stated.
"But you get a science geek in a lab with all their fancy instruments and they prove that moisture does get in to the system. "
I don't want a food fight here but I don't think that this proof exists. If you think it does we'd like to see it.