getting the right size vacuum pump

**chrashley** · 03-17-2008, 09:06 PM

What would be a good cfm of vacuum pump to have. I do only resi work. What are the best brands and why? Thanks!!

**weber** · 03-17-2008, 09:09 PM

I recommend the YJ 1.5, because its the best setup I have ever used.

**beachtech** · 03-17-2008, 09:46 PM

we use 5 cfm and 6 cfm pumps

**weber** · 03-17-2008, 09:47 PM

Originally Posted by beachtech

we use 5 cfm and 6 cfm pumps

Well, that explains alot

**BigJon3475** · 03-17-2008, 09:49 PM

I have a 3 cfm dual stage I think it's a bit to big for the systems I have. I would try and get the smallest dual stage possible.

**beachtech** · 03-17-2008, 09:57 PM

Originally Posted by weber

Well, that explains alot

i use what they give me

http://robinair.com/product-new/deta...=1061&catid=11

**mario_m** · 03-18-2008, 07:08 AM

This thread may help you:
http://www.hvac-talk.com/vbb/showthread.php?t=159232

Go to the JB website (jbind.com). There is plenty of literature available on selecting a vacuum pump that is right for you. Try to find a distributor of JB, they may let you test out some vacuum pumps. I'm currently testing a 7 cfm and a 3 cfm.

The most simple way to sum things up is that cfm doesn't mean a whole lot. Once the system reaches a vacuum, which is usually less than a couple minutes on small systems, a 1.5 cfm to a 10 cfm work pretty much the same.

**beenthere** · 03-18-2008, 07:28 AM

They work the same. But the larger one will still be drawing quicker. The primary is still bigger.
If you draw too quick, you could form ice crystals.

**bdivell** · 03-18-2008, 07:40 AM

I personally use a 6 cfm Yellow Jacket and have a never had a problem with it very easy to use and quick

**beenthere** · 03-18-2008, 07:47 AM

I use a 6 also.
Have seen a lot of guys use 7's.

No need for a large vac, for small resi stuff though.

**BigJon3475** · 03-18-2008, 07:51 AM

All I work pon is small residential sized systems. I have to play with the ballast within a few minutes to keep it around the 3000-5000 microns.....I'd rather it take a little longer to make sure it's not forming crystals instead of boiling off.