Cheap/Easy DIY Degassing Vacuum Pump

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antherzoll

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Hello

First off, this is my first post! So hi everyone. I've been lurking for years and have always found great answers to my questions through searching, thanks for being such an awesome community. Thought I would use my first post as a contribution. I don't plan on being too active in the community, but I thought that this was worth sharing. One of my other hobbies involves me being in junkyards quite often to pick apart vehicles so that I can fix or upgrade my own. I'm also a born and raised homebrewer.

Right now I have 14 gallons of Pinot Noir that I need to degas. Usually I'd use the whip on the end of a drill but was looking into purchasing a vacuum pump... So I got thinking. Most vehicles come equipped with a vacuum assist pump with a vacuum switch. The pump is supposed to create enough vacuum to keep the brake assist functioning properly when engine vacuum is low. Somewhere around 0.5bar/15"hg. So I pulled one out of a vehicle along with the vacuum switch and a bunch of hoses to work with all for $30, only other thing required is a 12vdc 10amp power supply. The model I pull the parts from was a 2008 Volvo C30 T5, but I have seen this same setup in many other vehicles. These pumps have to operate in extreme condition so I'm sure that they are up to the task.

IMG_20190131_195623.jpeg


And I was able to create.

IMG_20190131_233620.jpeg



I'd still like to fix it up a bit, but it works! Switches on once a minute for less than a second.

What's required:
- Vacuum Assist Pump w/fittings (blue circle)
- Vaccum switch with connector and fittings (yellow circle)
- Check valve from braking circuit (green circle)
- hoses
- fittings for the carboy.
- 12VDC 10Amp Power Supply (can be purchased through amazon)
- Gauge (optional)

Screenshot_2019-02-01-00-57-53.jpeg


Pretty self explanatory. Make sure to wire the pump with the correct polarity. I plan on cleaning it up a bit and installing a fuse just because, but for now it's working well. Let me know what you all think.

Cheers
 
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Blacksmith1

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Genius! I have been looking at 12v pumps on ebay and haven't found one yet that I feel is what I want. I'm curious though, "they" say the magic # is -23psi for degassing. this works out to -7.2. Are you sure it gets it all out? this pressure would be much kinder to my plastic carboys.
 
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antherzoll

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I'm new to vacuum degassing, haven't had much time to read into it so I have no clue at what temperatures and pressures are acceptable. I was going to read into it a bit more but if anyone can provide links with information that would be great.

While the vacuum switch is not adjustable, it is just a spring loaded diaphragm valve. If you were able to open it without damaging you can increase the spring tension to get a stronger vacuum. I have popped them off accidentally while working on cars so it is not that hard to get them open, may need some JB weld to seal it up after.
 

Blacksmith1

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start on this site. just search vacuum. I don't remember where all I looked but most of my usable results where on here.
any idea how much pressure this type of pump can pull?
 
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antherzoll

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start on this site. just search vacuum. I don't remember where all I looked but most of my usable results where on here.
any idea how much pressure this type of pump can pull?
The pump is a Hella UP28. From my testing running the pump at full load it was able to pull a maximum of 21" quite easily. It also draws 6-7amp at 12V tested with my amp meter. It's operating range is 9-16v so if you wanted to get more work out of it you could up the voltage, but you would also need to up the ampacity of the circuit.
 
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Blacksmith1

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I'm setup for 12v don't want to screw with getting other psu's. your post seems to say 21 inch. not sure how to translate that into psi. the converter I found for PSI (relative to atmosphere) to inch of water column (relative to vacuum) says that my projected 23 PSI = 1043.4202923413913 inches
 
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antherzoll

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Not sure how/why you're using psi, but anyways, in-HG is roughly half of PSI. Using absolute PSI, a perfect vacuum has a PSIA of 0. At sea level atmospheric pressure is PSIA 14.7 which equals 1 atmosphere. 1bar = 14.5 PSIA

If we were using gauge PSI, then 0 PSIG = 1 atm = 0inhg. If we pulled a perfect vacuum the maximum negative PSIG we could pull is -14.7PSIG which equals 0 PSIA = 29.9in-HG = 0 atm. I don't understand how you're getting such low negative numbers unless you're calculating for a black hole. [emoji16]
 
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antherzoll

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Maybe this helps.
Screenshot_2019-02-01-11-23-13.jpeg


I always input inHG as a positive value that reference negative pressures, but the calculators want a ( - ) to calculate negative values. I guess the proper unit is ( X in -HG ) where -HG reference a negative value.... Clear as mud [emoji16].
 

Blacksmith1

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I plugged it into the wrong calc. when I re read your original post I saw my mistake.
I'm using PSI because the info I'm basing the rest of my research on used it, and I'm familiar with it. All these other gauges are foreign to my experience.
so with the right one 23 PSI= 46"hg (approx.)
This is a cheap enough setup that I might just give it a go and see if it will do everything I want. Vac transfer etc.
 
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antherzoll

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I plugged it into the wrong calc. when I re read your original post I saw my mistake.
I'm using PSI because the info I'm basing the rest of my research on used it, and I'm familiar with it. All these other gauges are foreign to my experience.
so with the right one 23 PSI= 46"hg (approx.)
This is a cheap enough setup that I might just give it a go and see if it will do everything I want. Vac transfer etc.
Pressure and flow are not the same thing. This pump might be insufficient for vacuum transfer. While it may have enough working pressure to pull a column of water 285in, there is no specification on flow rate. Judging by the system that this pump was designed for there is very little volume for it to work on, so transfer rate maybe very slow. You will have to do your own testing. As for overworking the motor, I have seen these vacuum pumps run continuously for hours under engine hoods due to a broken vacuum switch without failure, so while it may be slow I believe it is still durable enough for the task.
 

Jayjay1976

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Aren't you at all concerned about the glass carboy imploding under the vacuum? Seems dangerous to me, but this isn't my area of expertise. I suppose the video above proves it didn't happen, I just don't trust glass under a vacuum.
 
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antherzoll

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If it was plastic I would. If it was a lesser quality carboy then I would also be concerned. I am quite confident with the car boys that I'm using that they are able to hold vacuum pressure. A quick search shows people are using their vacuum setups on glass carboys to as low as 23", that's a bit much for my liking, I will likely degas down to 18-20".
 

Blacksmith1

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there are a couple members here that have a $200 vac pump setup that does degassing, transfer, and bottling. it pulls -23 psi IIRC. I'd like to have a similar setup for a lot less money.
 
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antherzoll

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Aren't you at all concerned about the glass carboy imploding under the vacuum? Seems dangerous to me, but this isn't my area of expertise. I suppose the video above proves it didn't happen, I just don't trust glass under a vacuum.

Here is one example of a guy using a refrigerant vacuum pump to degas. These pumps are capable of pulling a vacuum close to absolute. That's strong enough to cause the alcohol and water to boil. [emoji33]
 
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antherzoll

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there are a couple members here that have a $200 vac pump setup that does degassing, transfer, and bottling. it pulls -23 psi IIRC. I'd like to have a similar setup for a lot less money.
I'm still not understanding how you're using PSI. Maybe they are mixing up their units? On some PSI gauges, positive is in PSI, negative values are in inHG.

Screenshot_2019-02-01-20-12-05.jpeg
 

Blacksmith1

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Go big or go home! I think I'd rather try my Ozark Mountain Air pump for the air mattress before I did that.
 

Blacksmith1

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Ok, while looking for the info I found enough threads and post with other info to make me think I screwed up the numbers somehow. It is possible that was the level they suggested one does not pass for safety due to the chance of implosion. I really need to start saving some of these links so I can get back to them.
 
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antherzoll

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More testing.



Here is is running at full load. The degassing CO2 is keeping press at 18" seems to be working well enough.
 
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antherzoll

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So I left the pump running for about 15mins. Was still running strong but the output did drop a bit to 16in-HG as it got hot. Measuring the pump temp it was up to 95*C... Hot, but not worrisome as again, these pumps operate under the hood of a motor vehicle in the heat of summer in places like Arizona[emoji91]. I opened up the vacuum switch and adjusted the spring tension by stretching it out and cutting off a few coils. It now switched off at 17" and on at 15". Runs once every 30 seconds for 1 second. Much easier on the pump and I can set it and forget it.

Now for time. I know a stronger vacuum will scavenge more out of solution faster, but how long should these run for? I figure for as long until it reaches a stable pressure without any signs of visible bubbling. So far with the current setup it's been running for about an hour and is still degassing. I'm in no rush, just curious of others experiences with this. I guess with a powerful enough pump I could get into vacuum distillation [emoji16].
 

AZCoolerBrewer

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One of the things that has kept me from trying to make mead has been the degassing schedule early in the process. With something like this, I think it might be workable.
 

RPh_Guy

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Holy unit conversions Batman!
it was able to pull a maximum of 21"
I'll assume you're talking about inches of mercury.

21"Hg = 0.71 bar = 10psi = 285" water

the magic # is -23psi
47"Hg = 1.6 bar = 23psi = 640" water

Whether the units are positive or negative doesn't matter. That just tells you the direction of the pressure.
this pressure would be much kinder to my plastic carboys.
No, it won't. Plastic will collapse under much lower pressure.

Aren't you at all concerned about the glass carboy imploding under the vacuum?
Yes, it's recommended to have the carboy nearly full to reduce the force on the glass.
One of the things that has kept me from trying to make mead has been the degassing schedule early in the process. With something like this, I think it might be workable.
The mead also needs aerated. A drill-powered stir tool is easy to use and takes maybe 5 minutes or less in my experience.
 
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antherzoll

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Well... Seems like the power supply is weak. Used a cheap one that I had on hand. Metered the voltage when the pump is running and voltage drops down to 9-10V, quite significant and it will affect the pumps output. I'll wire it to a proper power supply and take better measurements when I get a chance.
 
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antherzoll

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I've been busy.

Finally got it hooked up to a better power supply.

IMG_20190208_222908.jpeg


It sucks! [emoji16]

Already degassed most of my wine and it works quite well. It may also work well as a vacuum transfer pump at the flow seems improved with the step up in voltage.
 

Bilsch

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Man if you'd have ever seen glassware in a lab implode under vacuum.. you wouldn't be doing this in a carboy. No no no no.. just no!
 
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antherzoll

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Man if you'd have ever seen glassware in a lab implode under vacuum.. you wouldn't be doing this in a carboy. No no no no.. just no!
Not too concerned unless they are damaged or of poor quality. Also, with such a small head space there little potential for a catastrophic failure and will more likely fail in a way that would result in a pressure crack, the carboy falling to pieces, and me loosing that volume of wine. That's why it stays in the sink just incase.
 
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antherzoll

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put a gallon bottle as a plenum just before the pump during transfer. Keeps any liquids out of your pump.
Thanks. Will do. Already sucked up some shmoo while degassing, but not to concerned. These pumps are designed to ingest engine air that comprised of fuel/oil vapours, combustion byproducts, and water vapor. Pretty sure they can eat it and keep working without issues. [emoji16]
 
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antherzoll

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Connecting the vacuum pump to a more accurate gauge.

IMG_20190304_161638~2.jpeg



Pump running at full it's able to pull -27inhg. I had my vacuum switch set a -25inhg. My carboys were able to hold the pressure and fully degas my wine. -25inhg is a bit much for degassing so I'll lower to -22inhg next time around, but regardless it was successful and done on the cheap. Bottled all of my wine last week and it tastes great.

IMG_20190224_174905.jpeg
IMG_20190224_224847.jpeg


Cheers!
 

NeverDie

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From what I've read you need to pull a minimum of 18 inches mercury in order to degass the carbon dioxide from your wine. Unfortunately, even then it doesn't happen quickly, but can apparently take up to 30 minutes for a 5 gallon carboy.

To avoid the implosion issue, I ordered this vacuum chamber (which arrived today):
https://www.amazon.com/gp/product/B07CJLVYKY/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1

That way I can put whatever non-sealed vessel I want inside it (including cheap PETE plastic 1 gallon spring water bottles from the grocery store that have been converted to fermentation vessels) for degassing without fear of causing implosion. Admittedly, though, the vacuum chamber itself is not as cheap or even convenient as what the OP did.

I'm impressed if the OP's vacuum pump can pull 21 inHg. I earlier tried one of the foodsaver vacuum pumps, which was of similar size to the OP's vacuum pump, but it really didn't pull enough vacuum to do a proper full degassing.
 
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antherzoll

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From what I've read you need to pull a minimum of 18 inches mercury in order to degass the carbon dioxide from your wine. Unfortunately, even then it doesn't happen quickly, but can apparently take up to 30 minutes for a 5 gallon carboy.

To avoid the implosion issue, I ordered this vacuum chamber (which arrived today):
https://www.amazon.com/gp/product/B07CJLVYKY/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1

That way I can put whatever non-sealed vessel I want inside it (including cheap PETE plastic 1 gallon spring water bottles from the grocery store that have been converted to fermentation vessels) for degassing without fear of causing implosion. Admittedly, though, the vacuum chamber itself is not as cheap or even convenient as what the OP did.

I'm impressed if the OP's vacuum pump can pull 21 inHg. I earlier tried one of the foodsaver vacuum pumps, which was of similar size to the OP's vacuum pump, but it really didn't pull enough vacuum to do a proper full degassing.
Nice chamber, but that's cost prohibitive for my setup, would rather spend that on more grapes [emoji16]

As for the pump, check my last few post and you will see that the pump is able to pull a vacuum down to -27inhg at full load. I do have a vacuum switch connected to it and plan on raising the setpoint to ~-18-20inhg next time I need to. So, previous to this my carboys were degassing at -25inhg for hours without issues or incident, I feel completely safe using this setup in the future to degas.
 

NeverDie

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Nice chamber, but that's cost prohibitive for my setup, would rather spend that on more grapes [emoji16]

As for the pump, check my last few post and you will see that the pump is able to pull a vacuum down to -27inhg at full load. I do have a vacuum switch connected to it and plan on raising the setpoint to ~-18-20inhg next time I need to. So, previous to this my carboys were degassing at -25inhg for hours without issues or incident, I feel completely safe using this setup in the future to degas.
Does your vacuum pump require oil (and give off smoke)? Apparently a lot of them do. Mine does, but it's not much.
 
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antherzoll

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No smoke, no oil. Even when left running at full load and as hot as 90C it does not let off a smell unless it injests some of the wine. Read through my previous post to get an understanding of the operating conditions that this pump is supposed to be working in. Also considering that Volvo designs their cars for safety, this pump has to operate in severe conditions without fail as it plays an important role in the safe operation of the braking system.
 

crabjoe

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Here is one example of a guy using a refrigerant vacuum pump to degas. These pumps are capable of pulling a vacuum close to absolute. That's strong enough to cause the alcohol and water to boil. [emoji33]
I've got one of these pumps because I used it when I replaced my AC unit. Looks like I'm going to need to look for some parts so I can use it to degas wine..

Anyone know where I can get a cheap vacuum regulator? Because as quoted above, these things can pull close to zero. If I remember correctly, when I pulled a vacuum on my AC system, it was down to 200-300 microns.
 
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antherzoll

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I've got one of these pumps because I used it when I replaced my AC unit. Looks like I'm going to need to look for some parts so I can use it to degas wine..

Anyone know where I can get a cheap vacuum regulator? Because as quoted above, these things can pull close to zero. If I remember correctly, when I pulled a vacuum on my AC system, it was down to 200-300 microns.
https://canada.newark.com/multicomp/psf109s-81-330/pressure-switch-spdt-11-9psi/dp/24R7147

I've used this switch on my setup and adjusted it to 18-in/hg and it's works well at maintaining the setpoint. Of course, your going to get a lot of foaming at first so you should trigger it manually and monitor to keep it from ingesting too much wine.
....
 

mrian

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From what I've read you need to pull a minimum of 18 inches mercury in order to degass the carbon dioxide from your wine. Unfortunately, even then it doesn't happen quickly, but can apparently take up https://www.amazon.com/gp/product/B07CJLVYKY/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1

Hi, just seen your post and registered on the forum. I ordered the same vacuum chamber and I’m about to take the must off and degas. Do you find the pump smokes a lot? I’m thinking I may need to run the pump longer and let it break in a bit. I’ve not found many useful videos on the process and when I get round to it, I’ll upload one to the forum.
Any tips using the chamber would be welcome.
 
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