DIY Cold Crash Protector

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Matthopperman

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I've been looking at rigging something up to protect from oxygen for cold crashing. I know some people just tie a little mylar balloon to a tube or something similar, but I'm looking to rig up something like the cold crash guardian. I came across this video which basically replicates one:

The only thing is, as with all American to Australian conversions, I'm struggling finding equivalent parts that will work together with the threading, etc, and am struggling to find certain pieces at all.

So far my shopping list is:

- Spigot (I actually already have a couple of these, but the link are the ones I have): Fermenter Tap - Adjustable spout with bulkhead (24mm hole) | | KegLand

- Tubing: https://www.bunnings.com.au/pope-10mm-x-5m-clear-vinyl-tubing_p3130565

- Elbow fitting: https://www.bunnings.com.au/gcon-10mm-clear-vinyl-tube-fitting-elbow-connector-5-pack_p3130767

- T fitting: https://www.bunnings.com.au/gcon-5mm-clear-vinyl-tube-fitting-t-piece-connector-5-pack_p3130759

- No return valve fitting (though hopefully can find something local to avoid having to wait for shipping): https://www.aliexpress.com/item/1005003710686092.html

- Water bag (the smaller size): 3 Packs Water Storage Carrier Bag, Premium Collapsible Container 5L (1.3 Gallon) BPA Free Food Grade No-Leak Freezable Foldable for Camping Hiking Backpack Emergency : Amazon.com.au: Sports, Fitness & Outdoors

But one part in that video (8:50 he talks about both parts) is the adapter he uses to allow the spigot to be attached to the lid without the nut of the spigot getting in the way when the cap is then screwed back onto the water bag. Then either a cap or bushing attaches to that adapter (I think in lieu of the nut that comes with the spigot, since needs to be a male attachment with the adapter). It doesn't look like Bunnings has either attachments. The adapters they sell seem to be threaded on one side and the other side suited to a pipe to be pushed in.

If anyone knows where I could find those two remaining parts, something that would screw onto the spigots from Kegland, please let me know. And just generally if that shopping list checks out, or if I might run into issues. I'm not very handy with this stuff so I don't want to mess up the sizes or types of threads especially.
 
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Kmart do a collapsible water container which I’ve used on my chronicals in the past. The valve fits standard silicone tubing which is my blow off during primary fermentation.
 
Kmart do a collapsible water container which I’ve used on my chronicals in the past. The valve fits standard silicone tubing which is my blow off during primary fermentation.
Might be a bit big by the looks of it, but I wonder if that cap would fit a smaller bag, because that would save a lot of hassle having the tap already on the cap
 
Might be a bit big by the looks of it, but I wonder if that cap would fit a smaller bag, because that would save a lot of hassle having the tap already on the cap

I had some large temp variation cold crashes suck the bag completely in and that was a normal size batch in the chronical. So any smaller you’d end up sucking it in and then sucking air/oxygen in anyway defeating the purpose entirely… of course you can remove the bag and quickly fill with CO2 and reconnect as another option.
 
I had some large temp variation cold crashes suck the bag completely in and that was a normal size batch in the chronical. So any smaller you’d end up sucking it in and then sucking air/oxygen in anyway defeating the purpose entirely… of course you can remove the bag and quickly fill with CO2 and reconnect as another option.
I think the one-way valve would just create a vacuum in that case
 
I think the one-way valve would just create a vacuum in that case
You’re assuming it will be 100% no leak. I’m my experience with vacuum it’s extremely difficult to get a 100% seal. Just depends how much you endeavour to exclude air/oxygen. If you’re going to rely on the vacuum just have a one way valve at the start of the cold crash and forget the bag setup?
 
You’re assuming it will be 100% no leak. I’m my experience with vacuum it’s extremely difficult to get a 100% seal. Just depends how much you endeavour to exclude air/oxygen. If you’re going to rely on the vacuum just have a one way valve at the start of the cold crash and forget the bag setup?

I just mean to say in the event it did need to suck up more than say 3 litres worth of co2 (which from everything i’ve heard would be very unlikely), it wouldn’t be able to just suck back up the sanitiser. I don’t want to create a vacuum on purpose, just that that’s preferable to suckback of sanitiser.
 
If you look at the solubility of CO2 at temperature, any decent carbonation table should give you the answer.
This one on Braukaiser is my favourite. Note the dissolve CO2 at your fermentation temperature and at your cold crash temperatures, calculate the amount you need. Use the metric table makes it easy, multiply by the litres of beer and you will have the mass of CO2 you need.
Number of Moles=Mass/Formula weight (44g/Mol for CO2)
Solubility of CO2 at 20oC is 1.7g/L
Solubility of CO2 at 0oC is 3.2g/L
So you need 3.2-1.7=1.5g/L
If your batch was say 20L you would need 20*1.5=30g

From the above No Mol = 33/40 = 0.825 Moles
At STP (Standard Temperature and Pressure (0.0oC & 1 Atmosphere or zero gauge pressure)) 1 Mole of gas will occupy 22.414L.
You need 0.825 Moles so you need ~18.5L
That’s just to account for the CO2 that will go into solution. Allowing a bit for contraction of gas in headspace and tubes, insurance... I would be wanting to have around 1L of store CO2/L of beer in the fermenter, any less and you’re just playing with yourself.
Mark
 
Hey Matt, I've been experimenting with mylar balloons and there were discussions on how large they need to be and weather the CO2 produced during fermentation produces other byproduct gasses which can contaminate the beer etc, etc, etc,. Well, after some consideration I found that My mylar balloon which is about 3 litres doesn't fully empty durring cold crashing. It is just attached to a tube which is inserted into a grommet the same size as the one for the bubbler and it doesnt leak. infact the balloon fills up tight and then any additional gas starts releasing through the bubbler. I allow a day or two of fermenter activity before placing the ballon on, that way the O2 is pushed out by the creation of CO2. Now given everything I have read CO2 is heavier than O2 and forms a layer over the beer anyway so even during suck back the CO2 layer should protect O2 from coming into contact with the beer. but the mylar balloon gives me peace of mind. That's my two bobs worth and it's been working for me without a hitch. I also add CO2 into my bottling bucket before transfer as well as giving a zap into each bottle before capping. for me it has been simple and easy.
 
I found it easier to use two soft drink bottles, vinyl tubing and a couple of adapters, to make both a blowoff airlock, and a vacuume trap.

Tube it so sanitizer can flow from one of these two bottle to the other (not exit the airlock/vac-trap), and use enough sanitizer to ensure that one of the inner hoses is always submerged. But large enough bottles that it doesn't bubble to the top.

Can make this with PCO 1881 tee and carbonation caps, or with a smaller vinyl tubing double adapter.

You can prime with CO2 to attach late, just attached during fermentation.
 
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Seems easier to use two soft drink bottles, vynal tubing and a couple of adapters, to make both a blowoff airlock, and a vacuume trap.

Tube it so sanitizer can flow from one of these two bottle to the other (not exit the airlock/vac-trap), and use enough sanitizer to ensure that one of the inner hoses is always submerged. But large enough bottles that it doesn't bubble to the top.

Can make this with PCO 1881 tee and carbonation caps, or with a smaller vinyl tubing double adapter.

You can prime with CO2 to attach late, or if out on during fermentation it collects its own.

That doesn't sound easier to me at all, and your instructions are very confusing. I mostly just want to know if the parts I linked are the equivalent to the parts he uses in the video, plus some help tracking down some of the stuff he uses I can't find.
 
Hey Matt, I've been experimenting with mylar balloons and there were discussions on how large they need to be and weather the CO2 produced during fermentation produces other byproduct gasses which can contaminate the beer etc, etc, etc,. Well, after some consideration I found that My mylar balloon which is about 3 litres doesn't fully empty durring cold crashing. It is just attached to a tube which is inserted into a grommet the same size as the one for the bubbler and it doesnt leak. infact the balloon fills up tight and then any additional gas starts releasing through the bubbler. I allow a day or two of fermenter activity before placing the ballon on, that way the O2 is pushed out by the creation of CO2. Now given everything I have read CO2 is heavier than O2 and forms a layer over the beer anyway so even during suck back the CO2 layer should protect O2 from coming into contact with the beer. but the mylar balloon gives me peace of mind. That's my two bobs worth and it's been working for me without a hitch. I also add CO2 into my bottling bucket before transfer as well as giving a zap into each bottle before capping. for me it has been simple and easy.
Yeah, that kind of basic balloon setup you mention is basically how this would work but without needing a second hole for it.

What do you use to zap co2 into each bottles?
 
That doesn't sound easier to me at all, and your instructions are very confusing. I mostly just want to know if the parts I linked are the equivalent to the parts he uses in the video, plus some help tracking down some of the stuff he uses I can't find.

Yeah makes sense not to change horse midstream.

Sorry for the poor explanation. Posting a diagram of the concept for those interested - might make a bit more sense.

By "fermenter volume changes" i mean of the liquid not the vessel. E.g. cold crashing.

Screenshot_20230422-124414.png
 
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In my opinion a much easier solution is to just attach a carb cap to your blow off tube, and then a disconnect (gas/liquid) and a bit of tubing that goes into your jar (or whatever) of water.

As you start to cold crash either add a little CO2 to the fermenter via carb cap or wait until the water starts sucking up the tubing when cold crashing- disconnect the disconnect, bump the carb cap with CO2 and reconnect.

Added benefit is you can help with an 02 free transfer to kegs/bottles by putting some low C02 pressure into the carb cap while filling.
 
In my opinion a much easier solution is to just attach a carb cap to your blow off tube, and then a disconnect (gas/liquid) and a bit of tubing that goes into your jar (or whatever) of water.

As you start to cold crash either add a little CO2 to the fermenter via carb cap or wait until the water starts sucking up the tubing when cold crashing- disconnect the disconnect, bump the carb cap with CO2 and reconnect.

Added benefit is you can help with an 02 free transfer to kegs/bottles by putting some low C02 pressure into the carb cap while filling.
This is what I do with an old school HDPE fermenter - has disconnect in place of the airlock grommet. I usually do a gentle crash and top up with co2 every now and then.
 
Yeah makes sense not to change horse midstream.

Sorry for the poor explanation. Posting a diagram of the concept for those interested - might make a bit more sense.

By "fermenter volume changes" i mean of the liquid not the vessel. E.g. cold crashing.
Ah, yep, I follow you. That sort of setup does look good. Very handy diagram for people who wanna go that route.


In my opinion a much easier solution is to just attach a carb cap to your blow off tube, and then a disconnect (gas/liquid) and a bit of tubing that goes into your jar (or whatever) of water.

As you start to cold crash either add a little CO2 to the fermenter via carb cap or wait until the water starts sucking up the tubing when cold crashing- disconnect the disconnect, bump the carb cap with CO2 and reconnect.

Added benefit is you can help with an 02 free transfer to kegs/bottles by putting some low C02 pressure into the carb cap while filling.
I did consider some sort of co2 injection as it starts to vacuum, but honestly what you describe sounds way more complicated than what I'm setting up (plus I don't keg beer so I have no co2 canister setup) because you'd have to add co2 as it contracts or almost sucks up the sanitiser rather than just letting a balloon fill up and ignoring it beyond that. But I may be misunderstanding what kind of setup you're talking about.
 
But one part in that video (8:50 he talks about both parts) is the adapter he uses to allow the spigot to be attached to the lid ...
If anyone knows where I could find those two remaining parts, something that would screw onto the spigots from Kegland, please let me know.
It's been 3 months but in case you're still looking, I think you mean:
Garden Rain 3 / 4" Poly Irrigation Plug (https://www.bunnings.com.au/garden-rain-3-4-poly-irrigation-plug_p3100137)
Garden Rain 0.75" Poly Irrigation Socket (https://www.bunnings.com.au/garden-rain-0-75-poly-irrigation-socket_p3100164)

...for any other type of those parts search Bunnings for the term: Garden Rain poly irrigation
That's how I find my 15mm, 1/2" (& the spaced 1 / 2"), 0.5" stuff. The terminology is not consistent but that search term will point you the right way.

[EDIT:] All my stuff is 15mm (1/2") so I'll add the other terminology worth knowing (socket, bush, nipple, cap & the above plug):
Garden Rain 0.75 x 0.5" Poly Irrigation Reduce Socket (https://www.bunnings.com.au/garden-rain-0-75-x-0-5-poly-irrigation-reduce-socket_p3100185)
Garden Rain 0.75 x 0.5" Poly Irrigation Reduce Bush (https://www.bunnings.com.au/garden-rain-0-75-x-0-5-poly-irrigation-reduce-bush_p3100175)
Garden Rain 3/4 x 1/2" Poly Irrigation Reduced Nipple (https://www.bunnings.com.au/garden-rain-3-4-x-1-2-poly-irrigation-reduced-nipple_p3100189)
Garden Rain 3 / 4" Poly Irrigation Cap (https://www.bunnings.com.au/garden-rain-3-4-poly-irrigation-cap_p3100130)
[EDIT2:] you may prefer the 0.75 x 0.5" Reduce Socket with a Garden Rain 1 / 2" Poly Irrigation Plug (https://www.bunnings.com.au/garden-rain-1-2-poly-irrigation-plug_p3100135) so that it may fit better into the lid at the 10:00 video position.
 
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