# Vacuum Pumps for fluid transfer

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#### Bsquared

##### Supporting Member
HBT Supporter
Has anyone had experience with using a vacuum pump to create a negative pressure in the vessel you are transfering to? I use a hand pump now to get my gravity feeds going,from the 6gallon primary to the 5gallon secondary , but I'm going to start brewing 15 gallon batches soon, and was thinking that I'm not going to want to lift or move that amount of beer manually.

I am thinking of building an insulated enclosure around a 15gallon cone bottom fermenter, that would be elevated over a second enclosed 15gallon cone bottom fermenter. I am thinking of using a vacuum pump to pull or suck the wart up into the top fermenter for the primary and then use gravity and one valve to transfer to the secondary below.

Any idea on how strong the pump would need to be to elevate 15gallon's 4 to 6 feet? Should I just look in to a self priming pump?

#### Bobby_M

##### Vendor and Brewer
Why not use pressure on the donor vessel? Use CO2.

Anyway, the volume you're trying to move has no bearing, it's all about how much the liquid inside the tubing between the two liquid levels weighs. That's a lot of math.

OP
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#### Bsquared

##### Supporting Member
HBT Supporter
Bobby_M said:
Why not use pressure on the donor vessel? Use CO2.

Anyway, the volume you're trying to move has no bearing, it's all about how much the liquid inside the tubing between the two liquid levels weighs. That's a lot of math.

I am thinking of having the wort pulled from the kettle through the CFC, up to the primary fermenter, for a minimal contamination risk.

I get that a 5foot 3/8in column of wort at 1.07 SG, would be roughly 4.09Lbs. I'll do some more math to check that and determine the negative pressure needed to lift that, but I don't think it will be too much.

#### Bobby_M

##### Vendor and Brewer
So... if it's 4 pounds of liquid, you now have to figure out how many square inches of area is.

((.375/2)^2) x Pi is .11 square inches. So .11psi neg pressure would hold that liquid in the column so 2-3 psi vaccum would probably do it if you figure in line resistance. Maybe my math is way off.

#### Lil' Sparky

##### Cowboys EAC
Bsquared said:
I am thinking of having the wort pulled from the kettle through the CFC, up to the primary fermenter, for a minimal contamination risk.

If this is what you're doing, and unless I read this wrong, then look no further than a wort wizard. Or you can pick up the \$7 version from your local petsmart in the fish/aquarium section. Only catch, you have to use a glass carboy with a carboy cap to make it work.

#### Bobby_M

##### Vendor and Brewer
Or some other non imploding recipient container. The reason the wizard works well is because you're already running your coolant water. It wouldn't be as cool if you're just trying to do a vessel to vessel transfer of already fermented beer cuz it would waste water.

OP
OP

#### Bsquared

##### Supporting Member
HBT Supporter
Lil' Sparky said:
If this is what you're doing, and unless I read this wrong, then look no further than a wort wizard. Or you can pick up the \$7 version from your local petsmart in the fish/aquarium section. Only catch, you have to use a glass carboy with a carboy cap to make it work.

Sweet thanks, you got me thinking. We have things like that in the lab, but they waste a lot of water, and here in the west thats a big no no.

But I can incorporate it into my recirculating CFC, and have the same effect, with no need for a vacuum pump, I can just use my sump pump. I can put a wort In and an air out on line on the fermenter, and Ill be set.