Letting CO2 into a 5L mini-keg (on the cheap!)

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The-Engineer-That-Brews

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For folk on a tight budget, the 5L refilling the steel mini-kegs of the type that most prepackaged beer comes in (the ones made by Huber) can be an attractive option.

One factor when dispensing from these is that once you've let the air in via the top valve, you've got to finish the keg off relatively quickly before it goes off. Whether you view that as a problem or an opportunity is up to you ;)

For folk who would prefer a little more time to finish the keg off, it would be nice to be able to let in CO2 instead of air. Special CO2 injector taps are available that clamp to the top of the keg, but they are not cheap. Therefore people might be interested to know that the rubber bung is a good tight fit for the outside of a standard 1/4" push fit connector. A cheap one, like those you get with those fridge fittings multipacks, is ideal.

Note that as I've shown in the photo, you have to push the connector almost the way through so that it seals round the inner side of the bung. If you don't do that it'll leak via the internal air duct. You'll probably also want to fit an in-line tap (usually also also included in the pack) so you can control the flow of gas. You could connect it to, for example, a jar full of CO2 collected from your fermentation bubbler; or possibly even a mini-regulator and CO2 bulb, although you might want to superglue it in place if you're going to do that.

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Ashman

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Yep the internal air duct is a problem. I know it will leak with a 1/2 barbed fitting (shown in image).... I’ve switched to a 15mm to 3/8” converter Into 3/8 John guest tee and jab the 15mm right into the black bung of a live commercial keg. Ok so the thing sprayed like hell for a a second but then Managed to dispense out the rest of the keg using just an end stop rather than extra gas.
 

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terrym

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For folk on a tight budget, the 5L refilling the steel mini-kegs of the type that most prepackaged beer comes in (actually they are made by Huber) can be an attractive option.

One factor when dispensing from these is that once you've let the air in via the top valve, you've got to finish the keg off relatively quickly before it goes off. Whether you view that as a problem or an opportunity is up to you ;)

For folk who would prefer a little more time to finish the keg off, it would be nice to be able to let in CO2 instead of air. Special CO2 injector taps are available that clamp to the top of the keg, but they are not cheap. Therefore people might be interested to know that the rubber bung is a good tight fit for the outside of a standard 1/4" push fit connector. A cheap one, like those you get with those fridge fittings multipacks, is ideal.

Note that as I've shown in the photo, you have to push the connector almost the way through so that it seals round the inner side of the bung. If you don't do that it'll leak via the internal air duct. You'll probably also want to fit an in-line tap (usually also also included in the pack) so you can control the flow of gas. You could connect it to, for example, a jar full of CO2 collected from your fermentation bubbler; or possibly even a mini-regulator and CO2 bulb, although you might want to superglue it in place if you're going to do that.
Not all the minikegs supplied to breweries in the UK are made by Huber as you have indicated. Some are made by Fass Frisch.
The differentiators are Huber tap is pull and twist, vent as your photo, Fass Frisch vent as below (which needs to be destroyed if the entire bung is to replaced), and a pull, twist and button press dispensing tap.
1598461625467.png

1598461667102.png

1598462196584.png
 

Ashman

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Yeah I don’t think the ‘other’ type Bung with red outer can be used with the tapping devices without replacement grey bung.

When I looked at the fass-Frisch Tap sport it maybe possible to connect something Up to it....
 

The-Engineer-That-Brews

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Not all the minikegs supplied to breweries in the UK are made by Huber as you have indicated. Some are made by Fass Frisch.
The differentiators are Huber tap is pull and twist, vent as your photo, Fass Frisch vent as below (which needs to be destroyed if the entire bung is to replaced), and a pull, twist and button press dispensing tap.
View attachment 31613
View attachment 31614
View attachment 31615
I stand corrected! Thanks - I've only encountered the Huber ones :-)
 

Ashman

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If anyone is interested I dismantled the tap on the other ones. They aren’t great for re use because of the bung and the tap isn’t that robust.
 

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terrym

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If anyone is interested I dismantled the tap on the other ones. They aren’t great for re use because of the bung and the tap isn’t that robust.
I have got kegs with both types of bung/taps. The Fass Frisch taps as shown in your photos are much more difficult to use and seem to spray beer all over the place when dispensing under pressure. The Huber ones don't do that. Sadly I've got five FF kegs and only one Huber keg. asad1
 

Alux

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Sorry to resurrect an old thread.

Anyone able to offer a component list to build something like the above? I've got a party star deluxe but would like a second dispenser.

From what I can make out I'll need:
  • Mini CO2 regulator
  • John Guest T fitting 3/8"
  • Dip tube/pipe
  • Beer lines 3/8"
  • Picnic tap
  • 3/8" to 15mm John Guest adaptor (to seal around top bung)
I'm really strapped for space in my tiny house so considering a mini kegerator build with 5L mini kegs. I've not dealt with CO2 fittings etc. before.

Do I need some sort of non-return valve like the corny gas in/beer out posts?

Thanks.
 

Ashman

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Sorry to resurrect an old thread.

Anyone able to offer a component list to build something like the above? I've got a party star deluxe but would like a second dispenser.

From what I can make out I'll need:
  • Mini CO2 regulator
  • John Guest T fitting 3/8"
  • Dip tube/pipe
  • Beer lines 3/8"
  • Picnic tap
  • 3/8" to 15mm John Guest adaptor (to seal around top bung)
I'm really strapped for space in my tiny house so considering a mini kegerator build with 5L mini kegs. I've not dealt with CO2 fittings etc. before.

Do I need some sort of non-return valve like the corny gas in/beer out posts?

Thanks.
Sorry missed this. I will need to check but I remember had a reducer 3/8 to I forgot maybe 3/16 and ran the beer line through it into the 3/8 tee with 3/8 end cap on other end. The stainless straw I forgot the measurement had a siphon pipe off cut in it to hold it in place but to be honest is just to pierce the keg and seal on the barb. I couldn’t tap the keg with just the 3/16 line. I had two connectors 3/8 x 15mm barb and 3/8 x 1/2 barb. From memory that the 1/2 didn’t seal in the black commercial keg bung. When I tapped the keg I got a fountain of beer that hit the ceiling! Not sure what the tapping method was with party star ( let all the gas out)?) but I had to get the thing down before a huge beer fountain erupted.

oh and removing the end cap
On the tee as I didn’t have return valve resulted in a fountain there too :)
 

stripeyjoe

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This cost about £15, would be cheaper if you can source a cheap dip tube... have swapped the 100mm nipple for a 60mm one, much better fit.
1x1/4” female equal elbow
gas in and liquid out posts with 1/4” male threads (or you could use John Guest for the gas in, as per the photo)
60mm nipple
long dip tube, cut it to length.
ptfe all threads and screw up tight.
AB0C8206-DA87-462B-9155-B919CC56D6C5.jpeg
 

Ashman

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This cost about £15, would be cheaper if you can source a cheap dip tube... have swapped the 100mm nipple for a 60mm one, much better fit.
1x1/4” female equal elbow
gas in and liquid out posts with 1/4” male threads (or you could use John Guest for the gas in, as per the photo)
60mm nipple
long dip tube, cut it to length.
ptfe all threads and screw up tight.
View attachment 45547
What’s the dip tube? 3/8 of stainless? I used stainless straw as the length was ok ish. I can’t remember the od. Though I did browse straws in tk maxx
 

stripeyjoe

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What’s the dip tube? 3/8 of stainless? I used stainless straw as the length was ok ish. I can’t remember the od. Though I did browse straws in tk maxx
Hi Ashman,
it was just a corny dip tube cut to length with a pipe cutter (same little ones as plumbers use), fits perfectly into the beer out post.

I got it from here, had to get a long one as they didn’t have the short one in stock. Did have to cut it down to where the bend is to get through the equal elbow.
 
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