Degassing with Air Vacuum Pump

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I3igDmsu

Junior
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I am new to wine making and hoping to build a simple vacuum pump to degass in a glass carboy from things I already have:
The air vacuum pump says it will achieve 28.3inHg at 90psi. From what I've read, you need about 20inHg to degas. I was planning on hooking the air vacuum pump to a compressor at around 60psi and upping it slightly until I start seeing bubbles form.

Thoughts on this method?
 
Thoughts on this method?

Yes: Wear earplugs!

Your setup sounds reasonable to me. I might think about getting something different than the orange carboy cap. I use a standard universal bung, and then I put a smaller drilled stopper (with a tube) into this well of the bung. I can then easily break vacuum by lifting up the stopper out of the bung.
 
Good price but I would be concerned that it did not have a pressure control and it being able to pull almost 30in HG.

I will make a suggestion. Maybe some will not like it due to oxygen exposure but you could use that pump for splash racking. Get a racking cane, cut it in half (you don't have to cut it but it would be neater), stick the cane in the orange carboy top so that the curved end is inside the carboy, aimed at the side of the carboy. Then vacuum the wine into the carboy with the wine splashing against the side. This will really help in degassing.

If you wanted to, instead of reracking again, you could use a brake bleeder to finish if you needed to.
 
How are you using this product ? Are you lifting the carboys and bringing them to the garage or brining the noise inside the house ?

Yes I would recommend a gauge and a valve to control vacuum pressure.

I do sell the flex racking cane with whatever size bung you may need - check my website for more information.
 
Although it can create 28 inHg, it doesn't say how much air it can pull. It uses 4.2 CFM. If I have my calculations right, you might get 0.5 CFM on the vacuum side. That might be ok for in-place degassing (and take forever), but seems a little slow for transferring (like the AIO does).
 
Although it can create 28 inHg, it doesn't say how much air it can pull. It uses 4.2 CFM. If I have my calculations right, you might get 0.5 CFM on the vacuum side. That might be ok for in-place degassing (and take forever), but seems a little slow for transferring (like the AIO does).

Rich
You are so correct - I did a seach for conversion and .5 cfm comes out to 1 LPM

Yes I have one of these machines to pull a vacuum for ac - Yes they are loud and the air compressor runs alot to keep up with it. I would use it degassing , but only when using a gauge and a valve inline.
 
Rich
You are so correct - I did a seach for conversion and .5 cfm comes out to 1 LPM.

No, 0.5 cfm (cubic feet per minute) converts to 14.2 lpm (liters per minute).

If you don't believe my numbers, believe your common sense: imagine a space that is 1 ft x 1 ft x 1ft. How many gallons of milk (@ ~4 L each) do you think could fit in that space? Certainly not only 1/2 gallon, which is what your conversion would imply.

Actually, 0.5 cfm is not a bad flow rate. It is equivalent to transferring a carboy in 2 minutes.
 
Rich
I just rechecked it using a different conversion table and yes you are correct !

It was not making sense when I initially wrote it down
 
Actually, 0.5 cfm is not a bad flow rate. It is equivalent to transferring a carboy in 2 minutes.

It is not bad if the vacuum is already created, and it is merely keeping up. But, it is creating the vacuum as wine is flowing in. so, you need a much faster flow rate.
 
It is not bad if the vacuum is already created, and it is merely keeping up. But, it is creating the vacuum as wine is flowing in. so, you need a much faster flow rate.

Well, now I am confused. I thought you calculated 0.5 LPM at 28 inches or so. if that is the case, then your comments about "keeping up" are not relevant. If the pump can deliver 0.5 cfm at vacuum (which is how I read your post), then that would be fine for final racking
 
Thanks everyone. I can easily put the compressor outside and run a line inside so the noise with be a lot less. I will be degassing in the house. It sounds like this will be a decent and low cost setup for degassing and should work without splash racking, but that is an option too. I dont have a gauge right now but will think about putting in a shutoff valve to control pressure. It sounds like it should work.

How long do you think it will take to Degas with this method?

Should I still use the clarifier and sulfites that the kit recommends and came with (not sure if these are affected if fully degassed but - I will be bulk aging the Mezza Luna Red for 6-9 mo+)?
 
I thought you calculated 0.5 LPM at 28 inches or so. if that is the case, then your comments about "keeping up" are not relevant.

If you are evacuating a sealed carboy, then yes, it will EVENTUALLY reach 28 inHg of vacuum.

Think of it this way: You have bathtub, and the water can drain at 5 GPM. How long will it take to empty a 20 gallon bathtub (reach 28 inHG)? 4 minutes.

Now, if you turn the faucet on, and the faucet fills the tub at the rate of 3 gpm, how long will it take to empty the bathtub?

More importantly, after 7 minutes, 21 gallons have come in (one tub = one carboy), and 35 gallons have drained out, leaving 6 gallons, or about 1/4 of a tub. So, you have only 3/4 of the potential vacuum by that time. If this were a vacuum system, on average, the wine would have experienced 3/8 of the potential vacuum during the splash degassing.

If the wine comes in at the same rate that the pump can take it out, then you never build any substantial vacuum.

If the pump can deliver 0.5 cfm at vacuum (which is how I read your post), then that would be fine for final racking

Fine for racking, but not necessarily degassing while racking.
 
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Thanks everyone. I can easily put the compressor outside and run a line inside so the noise with be a lot less.

I would still wear earplugs. My guess is that you will have a loud high pitched hiss of the gas. Not good for the eardrums.

How long do you think it will take to Degas with this method?

It all depends upon how much vacuum you can create in the carboy during the splash racking process.

Should I still use the clarifier and sulfites that the kit recommends and came with (not sure if these are affected if fully degassed)

Not that much related, other than degassed wine clears faster.

but - I will be bulk aging the Mezza Luna Red for 6-9 mo+)?

If you plan to bulk age 9+ months, then don't worry about degassing (the CO2 helps protect the wine), and clarifiers (time will do it for you).

K-meta is always needed.

K-sorbate is only needed when backsweetening.
 
Thanks richmke. Now that I think about it, what if I only let this one bulk age for 6 months and then bottle? Should I add Chitosan, K Sorbate? What about degassing now?

I was thinking about topping off with a $2 buck chuck Shiraz, will this work and how much headspace should I leave in the carboy for bulk aging?
 
Thanks richmke. Now that I think about it, what if I only let this one bulk age for 6 months and then bottle? Should I add Chitosan, K Sorbate? What about degassing now?

I was thinking about topping off with a $2 buck chuck Shiraz, will this work and how much headspace should I leave in the carboy for bulk aging?

If you are not backsweetening, you can safely omit the K-sorbate. I think whether you add the chitosan or not is up to you. (You should add k-meta.)

Topping off with two-buck Chuck is fine. You want to get rid of most of the headspace, so add enough wine to get the level up to at least the bottom of the neck of the carboy.
 
was thinking about topping off with a $2 buck chuck Shiraz,

Alas, 2 Buck Chuck is now 3 buck Chuck!
 
Thanks richmke. Now that I think about it, what if I only let this one bulk age for 6 months and then bottle? Should I add Chitosan,

I, personally, would skip it. Let time do the work.

K Sorbate?

If you don't back sweeten, you don't need it.

What about degassing now?

I would leave it alone, and let your rackings and time do the work. You can always degass prior to bottling, if it needs it.
 

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