vac purge method and pump size: one vs two stage

I have a passive closed loop system from bvv and am looking into getting a 5 gallon shatter vac set up to purge with. Ive found multiple conflicting opinions regarding one vs two stage and different cfm ratings. My questions are : one or two stage? Pros and con's. As far as I can find the main difference is microns it pulls and THC boils at room temp with either. The two stage pulls it faster but also at higher temps? At least that is my basic understanding. Also can anyone help explain the cfm rating?

And if anyone wants to chime in with the their method of using a vac chamber your input would be greatly appreciated. The tentative plan is to run the closed loop, spread the oil thin, place in chamber at full vac between 85-115 and pull and release until muffining stops. I have found so many different methods I do not know where to begin. When leaving it for 12-24 hours(as I will be doing large slabs) do I leave the heat on or simply vac? I intend on researching much more before but would love any second opinions or recommendations. Thanks all!

MinnesotaHomegrown303 said:

I have a passive closed loop system from bvv and am looking into getting a 5 gallon shatter vac set up to purge with. Ive found multiple conflicting opinions regarding one vs two stage and different cfm ratings. My questions are : one or two stage? Pros and con's. As far as I can find the main difference is microns it pulls and THC boils at room temp with either. The two stage pulls it faster but also at higher temps? At least that is my basic understanding. Also can anyone help explain the cfm rating?

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Either will work. We aren't under vacuum in a reactive temperature range to be an issue, but I prefer a 6 cfm or greater single stage for a closed loop system.

Heat isn't an issue, since we are just discharging the air.

WolfWurx uses a 6 scfm pneumatic Vaccon vacuum pump. It reaches -29.9" Hg using an air venturi, so has no moving parts and meets NEMA 7 electrical.

CFM ratings for pumps, are how many cubic feet of free air it will move per minute. As the atmospheric pressure falls under vacuum, so does the available air to pump, and as a result, the cfm.

I notice a typo and too late to edit. The Vaccon pulls a -29.5" vacuum, not -29.9" Hg.