Vaccing a system

[Darrenp]

Just wondering .. Any thoughts on using 2 x vac pumps on a vrv ..does this vac better /quicker .. Someone recently told me it doesnt do it any quicker as one vac cancels the other ??? Are they right ??

[install monkey]

1 vac pump- 3/8 line- schraeder cores removed- vac on both sides- with valves driven open-and use a torr gauge- u cant rush a vac- and more connections on a system could create issues- and who wants to lug 2 vac pumps to an outdoor- triple vac helps too and a long vac gives u a better sun tan:confused:

[Darrenp]

Ha ha .. Yeah I know all the above .. But was just wondering really .. Agree with lugging the two vac pumps about.. Just thought if you used two when pushed for time sometimes

[install monkey]

never use 2- my 2nd vac pump is in me shed-and stayin there- usually i vac for 24 hrs- - all good fun weatherproofin ur vac pump and placing access covers over the pump and weighing it down with nitro bottles!!

[passandscore]

"Depending on the system line sizes of large-tonnage systems, it is better to put two smaller, easily handled
pumps, at different locations. This will overcome some of the pressure drop problems and actually be faster than a single, large pump."

That quote is taken from a vacuum pump manufacturer.
http://www.jbind.com/marketing/Principles%20of%20Vacuum%20Presention.pdf