Propane Regulator for Cold Crash?

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matt_m

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A couple posts I read today got me thinking...why not use a standard low pressure propane regulator to supply CO2 to a fermenter during a cold crash?. Turning a standard CO2 regulator down that far doesn't really work but these are designed to work reliably at 11" WC (about 0.4 PSI) which would be fine for about any fermenter. The regulators run about $10. Probably spend more than that on fittings but it seems like the whole thing could be built for under $25, maybe under $20. Anyone try it before?
 
You mean this...
3FCD493A-DCA0-4249-9636-29B8866A31F7.jpeg

Yep! @day_trippr nonchalantly mentioned doing this, and it was a WTF moment.

So, it has now become part of “the process”. Thanks again Dave!! :mug:
 
Nice. It seems much simpler than CO2 harvesting methods if you've already got a CO2 supply at your fermenters for pressure transfers.

Where did you find a regulator with a mounting bracket?
 
matt_m said:
Nice. It seems much simpler than CO2 harvesting methods if you've already got a CO2 supply at your fermenters for pressure transfers.

Where did you find a regulator with a mounting bracket?

Those are just 2 Stainless Steel U-bolts holding the LP regulator in place.

I utilize the canister CO2 when cold crashing. Prior to cold crash, I switch a couple valves to direct the CO2 produced during fermentation to a StarSan filled keg so I can purge the keg with free CO2. I then use that keg to do a closed transfer fill of the keg.
 
*Bump

Want to try this but have a couple of questions...

- Will a propane regulator be OK inside the fermenter at cold crash temps? For now, I don't want to drill holes/run lines thru my ferm chamber (chest freezer).

- Can anyone recommend a regulator AND appropriate fittings to connect to ball lock/gas in quick disconnect?

Thanks!
 
I never got around to buying one but on your first question, millions, maybe billions, of propane regulators sit outside in the winter.
 
- Will a propane regulator be OK inside the fermenter at cold crash temps? For now, I don't want to drill holes/run lines thru my ferm chamber (chest freezer).

What Matt said!

- Can anyone recommend a regulator AND appropriate fittings to connect to ball lock/gas in quick disconnect?

As far as a Low Pressure regulator, you can find those at any small or big hardware store...just get a low pressure one.

For fittings and connections, I utilized DuoTight and EVA Barrier Tubing. In my case, anything going in or out of the regulators (even the Ball Lock Gas quick connects) have to end with a 1/4” Male Flare Fitting, for these Fittings to work.
 
The regulator is nothing special, any simple single-stage will work. I have a Marshall for one fridge and this Camco for the other.

Both have 1/4" fpt input threads and 3/8" fpt output threads, and if you are using 1/4" female flare PTC fittings as I do , you'll need a hex nipple 1/4" mpt x 1/4" mfl, and a hex nipple 3/8" mpt x 1/4" mfl for the output. I happened to have a pair of the 1/4" nipples and a 3/8" to 1/4" reducing bushing on hand, so went with that, but if you're buying you can save a couple of bucks going with the nipples.

ferm_chambers_CO2_02.jpg


When needed I just insert the assembly in the gas feed. Love PTC fittings :)

Cheers!
 
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Quick question: Are flare washers still required with Duotight fittings? I believe they are but just double checking. A quick search led to conflicting info...
 
No, the Duotight (and John Guest and DMfit) female flare fittings have deformable mating surfaces that provide the function of a flare gasket.
Just don't over-tighten these fittings - especially the Duotights as they are prone to blow-out cracking just ahead of the flare threads.
Lubricate the tip for the male side, hand tighten the fitting, check for leaking (dunk test is best) and use a wrench to tighten slightly if needed...

Cheers!
 
This is one of those really elegant solutions that you can't help but appreciate...even if you have already partially solved it with your own expensive Rube Goldberg contraption. Sigh - wish I had seen this a few weeks ago :)

I guess one 'downside', depending on your setup, is the need to keep it connected to CO2. There's just enough room in my minifridge for the fermenter so tank would stay outside. I want to avoid drilling as well. Hopefully one of the EVAbarrier diameters will fit through the existing drip hole in the back of the fridge.

I didn't notice any inline filters. In general, do folks not worry about contaminants/infection from the CO2 tank at this stage? I see the filters on the oxygenation / aeration kits so assume at that stage, before pitching, it is more of a concern, but by the time you're about to cold crash, alcohol present, etc even a crawly or two wouldn't impact final product?

Can this much pressure also be used for a pressure transfer or do you just use QD's to take the propane regulator out of the line?
 
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I guess one 'downside', depending on your setup, is the need to keep it connected to CO2. There's just enough room in my minifridge for the fermenter so tank would stay outside. I want to avoid drilling as well. Hopefully one of the EVAbarrier diameters will fit through the existing drip hole in the back of the fridge.
8mm OD for both the 4&5mm ID EVA Tubing.

Yeah. I understand not wanting to drill through a fridge. In the end, for me, I had to get over my fear. Research....and even when extremely certain I wasn’t going to hit any lines, proceeded with caution. ( I used a bulkhead to go through the fridge)

I didn't notice any inline filters. In general, do folks not worry about contaminants/infection from the CO2 tank at this stage? I see the filters on the oxygenation / aeration kits so assume at that stage, before pitching, it is more of a concern, but by the time you're about to cold crash, alcohol present, etc even a crawly or two wouldn't impact final product?

I am not worried about anything coming from the CO2 tank and never gave any thought to have a need for an inline filter. So, no. I’m not worried about contamination.

Can this much pressure also be used for a pressure transfer or do you just use QD's to take the propane regulator out of the line?

I ferment using SS Brewbuckets. (Their gasket and latches can hold the 0.5 psi Of CO2) once cold crashing is complete, I disconnect my Fermenter from the CO2, place the fermenter on a table and place the CO2 purged keg on the floor. Create a closed loop to allow the beer to flow to the keg, and the CO2 to move to the fermenter. Pull the PRV on the keg and let gravity and the 0.5psi of CO2 to displace the liquid. No implosion, no explosion!
 
Got it - so the low pressure is enough for a gravity assisted sealed transfer without creating negative pressure on the inside of the fermenter. Slick.

And no concerns about CO2 interacting with the regulator components? Either over the short term to corrode something that ends up in the beer, or longer term to lead to regulator failure. I think certain gas regulators are interchangeable and others are not. Not sure about this scenario?
 
And no concerns about CO2 interacting with the regulator components? Either over the short term to corrode something that ends up in the beer, or longer term to lead to regulator failure. I think certain gas regulators are interchangeable and others are not. Not sure about this scenario?

I think these regulators are typically made of zinc. So corrosion isn’t going to be an issue.
 
My 1/2 bbl conical sits low to the ground. The max fill level of a keg would be about 8 or 9 inches above the lowest liquid level of the almost empty fertmentor. Would 0.4 psi (11" water column) be sufficient to complete a pressure transfer in a reasonable amount of time? Anyone done this without a gravity assist?
 
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