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General Category => Kegging and Bottling => Topic started by: darkmorford on June 06, 2011, 09:47:41 PM

Title: Just bought a CO2 tank...
Post by: darkmorford on June 06, 2011, 09:47:41 PM
I just got home with a 5 lb steel CO2 tank and dual-gauge regulator from the local welding supply shop. My plan is to use it with The Carbonater (http://www.liquidbread.com/) for now, and eventually I'll hook it up to a keg for my beer.

At this point I'm just wanting to make sure I have everything set up correctly. I used the yellow plastic washer that came with the cylinder and cranked the regulator on tight with a wrench. Then I opened up the valve on the tank and the high-pressure gauge read right around 800 psi. (Is this about normal for a 5 lb tank?) I didn't hear any gas escaping, so I think I've got it on right. I set the adjustment screw so that the low-pressure gauge read about 15 psi, then shut off the tank valve. As I understand it, if I leave it like that for a few hours and then check the gauges, they should read the same as they are now; any lower and I have a leak.

Am I on the right path here, or am I missing something?
Title: Re: Just bought a CO2 tank...
Post by: dbeechum on June 06, 2011, 10:20:29 PM
You're doing good.
Title: Re: Just bought a CO2 tank...
Post by: a10t2 on June 07, 2011, 02:03:10 AM
the high-pressure gauge read right around 800 psi. (Is this about normal for a 5 lb tank?)

It is if it's at 65°F. http://seanterrill.com/wp-content/uploads/2009/11/co2_pressure.png
Title: Re: Just bought a CO2 tank...
Post by: corkybstewart on June 07, 2011, 12:32:26 PM
Don't wait hours to check it-take a spray bottle of StarSan and coat all the connections.  If it leaks you'll see bubbles and you won't waste gas.
Title: Re: Just bought a CO2 tank...
Post by: hopfenundmalz on June 07, 2011, 12:39:50 PM
The plastic washer can slowly take a set.  Check the fitting agian in a couple of weeks.
Title: Re: Just bought a CO2 tank...
Post by: darkmorford on June 08, 2011, 03:23:07 AM
Well, I checked the gauges this morning. While neither was at zero—a Good Thing, I assume—the high-pressure gauge had dropped a little, and the low-pressure gauge had gone up by about 3 psi! I'm guessing it has something to do with the temperature fluctuating overnight?
Title: Re: Just bought a CO2 tank...
Post by: tschmidlin on June 08, 2011, 06:32:28 AM
The drop in the high pressure gauge makes sense if the temperature fluctuated a lot.  How much did it change?

The low pressure gauge . . . I'd keep an eye on it and hopefully it will stabilize.
Title: Re: Just bought a CO2 tank...
Post by: euge on June 08, 2011, 07:00:32 AM
Dude you are missing the whole point of the carbonator cap. Chill that beer and carb it up by shaking. Let the beer sit for about 10-20 minutes in the fridge and voila! Ready to drink or condition.

With the carbonator cap on and the beer level in the bottle at the "shoulder" of the bottle, squeeze it until it is empty of air. Then fill with co2 and the regulator on max (45 psi) and carb it up. Takes just a few shakes. You'll get of hang it.
Title: Re: Just bought a CO2 tank...
Post by: darkmorford on June 09, 2011, 11:51:16 PM
Thanks for the tips, guys. I'd had the tank sitting outside on my patio, so the overnight air temperatures were likely messing with the pressure. I've brought it inside where the temperature is more controlled and the whole thing seems to have stabilized pretty well. I don't actually have the carbonator cap yet—LHBS was sold out when I stopped in—so I've just been testing the connection from the regulator to the cylinder valve and the output valve on the regulator. Nothing leaking so far.

I do have a usage question about the cap, though. One thing I want to use it for is preventing a 2-liter bottle of soda from going flat. What sort of pressure should I be using for that? And once the bottle's filled with CO2, do I need to leave the carbonator on, or can I pull it and put the regular cap back on the bottle without losing too much fizziness?
Title: Re: Just bought a CO2 tank...
Post by: euge on June 10, 2011, 12:50:04 AM
I do have a usage question about the cap, though. One thing I want to use it for is preventing a 2-liter bottle of soda from going flat. What sort of pressure should I be using for that? And once the bottle's filled with CO2, do I need to leave the carbonator on, or can I pull it and put the regular cap back on the bottle without losing too much fizziness?

I let the bottle stabilize in the fridge for a few minutes and then vent the cap by pressing down on the poppit. 

I'm a shaker when it comes to the carbonater cap. It's no problem to do this at full psi, which is about 45 on these types of regulator.

Fantastic idea with recharging sodas. 

The carbonater cap is essential tool in my brewery. A great way to do quality checks on your brew right out of the fermenter.
Title: Re: Just bought a CO2 tank...
Post by: darkmorford on June 11, 2011, 07:11:50 PM
Okay, now this is just getting weird. Since I still don't yet have the carbonator cap—I'm going to (hopefully) pick one up later today—I shut off the tank valve last night and dumped whatever was in the regulator using the relief valve. Both gauges read 0 psi, and all the valves were closed. When I got up this morning, the low-pressure gauge was reading 5 psi! Somehow the system managed to build pressure with everything possible shut off.

What's going on here?
Title: Re: Just bought a CO2 tank...
Post by: tschmidlin on June 12, 2011, 05:20:56 AM
Is there a check valve between the keg and the gauge?  If so it might be leaking and so picking up the keg pressure.  It's also possible that the tank valve was not fully sealed.
Title: Re: Just bought a CO2 tank...
Post by: darkmorford on June 13, 2011, 12:48:39 AM
Check valve? No idea. I bought the regulator and tank from Central Welding in Redmond (up near Target and Home Depot), so it's whatever comes standard with what they sell. It's got the 0-2000 psi high-pressure gauge, 0-60 psi low-pressure gauge, a relief valve, and a 5/16" barb outlet with a shutoff valve. Maybe there's a check valve built into the shutoff, but I don't know and I don't know how to check. Incidentally, though, there's a "60" stamped on the relief valve. Just out of curiosity, I cranked up the regulator until the low-pressure gauge pegged (so it was definitely above 60 psi) and the relief didn't do anything. Faulty valve, or is this the wrong way to test it?

At any rate, I dumped the 5 psi that it was showing yesterday and 24 hours later it's still at zero, so there must have been something residual in the system somewhere. I've got the tubing and such I need for the carbonator on order, so hopefully they'll get here within the week and I can start playing around with it. I've got lots of ideas for stuff—mostly non-alcoholic—that would probably be better if it was fizzy. 8)
Title: Re: Just bought a CO2 tank...
Post by: darkmorford on June 18, 2011, 11:29:08 AM
Finally got the carbonator cap in today. Got it all hooked up, no leaks, then put about 30 psi of CO2 on a bottle of apple juice. That made it nice and fizzy; almost like a soda, but much healthier!

So much fun stuff I can do with this thing now...
Title: Re: Just bought a CO2 tank...
Post by: oscarvan on June 21, 2011, 01:52:22 AM
Is there a check valve between the keg and the gauge?  If so it might be leaking and so picking up the keg pressure.  It's also possible that the tank valve was not fully sealed.

He has no keg hooked up, yet.....if I read this all correctly.
Title: Re: Just bought a CO2 tank...
Post by: lupulin5446 on June 29, 2011, 11:03:48 PM
Just remember not to put the tank or regulator in a refrigerator with the beer. 
Title: Re: Just bought a CO2 tank...
Post by: richardt on June 29, 2011, 11:42:49 PM
Just remember not to put the tank or regulator in a refrigerator with the beer. 

Why do you say that?
Title: Re: Just bought a CO2 tank...
Post by: lupulin5446 on June 30, 2011, 02:57:57 AM
The adjustment apparatus on the pressure regulator usually contains a metal plate and spring that presses against a polymer seal.  Colder temperatures will change the properties of the spring as well as cause an inaccurate reading on the gauge.   
Title: Re: Just bought a CO2 tank...
Post by: tschmidlin on June 30, 2011, 03:23:57 AM
I've noticed problems with regulators in the fridge, thanks for the explanation.  Can you put any numbers to how far off it is and in which direction?  Usually it just creeps up on me, and won't stay where I set it.  Do you know the recommended operation temp for most gauges?  My garage swings from 38-90+ over the course of the year.
Title: Re: Just bought a CO2 tank...
Post by: narvin on June 30, 2011, 03:32:10 AM
This company lists the operating range as -40-+200 F for their regulators. 

http://www.manitowocfsusa.com/docs/uploaded/mbs/us/mbs/mbs_catalog/co2regulators.pdf

Of course, if your garage has temperature swings from 38 - 90, you'd be better off leaving it in the fridge because it will at least be constant.  If the temperature of the tank changes, so will the pressure and your regulator setting will also change.

I keep mine in the fridge and see no temperature drifts, nor do I have a problem balancing my system according to the standard chart.  YMMV, but it seems like something that's not worth worrying about.  If it's easier to put your tank in the fridge because of your setup, do it.
Title: Re: Just bought a CO2 tank...
Post by: tschmidlin on June 30, 2011, 03:36:14 AM
That's fine, but clearly not right in my experience.  I may have a different brand, but if I put them in the serving fridge then things get weird.  The serving fridge is warmer than -40F. :)
Title: Re: Just bought a CO2 tank...
Post by: lupulin5446 on June 30, 2011, 10:57:25 PM
When I studied draft systems at Seibel, the word was, 'do not put the regulator or tank inside a refrigerator'.  In addition to effecting the components of the regulator, the gas will become more dense.  I am certain that the regulator will function at a wide temperature range, but was it specifically designed for beer?  How is the accuracy affected?  1-2 psi make a big differance when carbonating beer.
Title: Re: Just bought a CO2 tank...
Post by: bluesman on July 01, 2011, 02:04:06 AM
I keep mine in the fridge and see no temperature drifts, nor do I have a problem balancing my system according to the standard chart.  YMMV, but it seems like something that's not worth worrying about.  If it's easier to put your tank in the fridge because of your setup, do it.

+1

I keep all of my CO2 tanks cold with the beer with no ill effects. A kegerator, a lagering keezer and a beer refrigerator all have their own CO2 tanks and no ill effects from any of them. I've even checked my regulator against a pressure gage installed to the keg and they are both within a degree of each other when set at 12psi.

I think the problem arises when you change your regulator setting, in that it takes some amount of time for the regulator pressure setting to adjust to the new setting and come into equilibrium with the actual beer pressure in the keg.
Title: Re: Just bought a CO2 tank...
Post by: tygo on July 01, 2011, 02:12:10 AM
I think the problem arises when you change your regulator setting, in that it takes some amount of time for the regulator pressure setting to adjust to the new setting and come into equilibrium with the actual beer pressure in the keg.

I think it just takes time for the gauge to read properly when it's cold. That may be what you mean.
Title: Re: Just bought a CO2 tank...
Post by: bluesman on July 01, 2011, 02:15:50 AM
I think the problem arises when you change your regulator setting, in that it takes some amount of time for the regulator pressure setting to adjust to the new setting and come into equilibrium with the actual beer pressure in the keg.

I think it just takes time for the gauge to read properly when it's cold. That may be what you mean.

Yes...it's late.  ::)
Title: Re: Just bought a CO2 tank...
Post by: narvin on July 01, 2011, 02:19:14 AM
When I studied draft systems at Seibel, the word was, 'do not put the regulator or tank inside a refrigerator'.  In addition to effecting the components of the regulator, the gas will become more dense.  I am certain that the regulator will function at a wide temperature range, but was it specifically designed for beer?  How is the accuracy affected?  1-2 psi make a big differance when carbonating beer.

I really can't comment on how the regulator's metal spring responds to temperature changes and affects accuracy other than what I've experienced.

However, the physics of CO2 dictates that it's liquid in the tank regardless, with gas "boiling" off as it is released.  The gas pressure coming out will be lower at lower temperatures, but I don't see why this would affect the output of the regulator.
Title: Re: Just bought a CO2 tank...
Post by: Tim McManus on July 01, 2011, 02:40:30 AM
PV/T=K

I've had a fridge with a 5# and 15# CO2 tank inside of it.  I've heard varying stories that the CO2 will deplete faster and other such wives tales.  I recently moved the CO2 tank outside of the fridge with a side modification (heck, I figured I could fit another keg in its place), and the only difference is the pressure reading for the tank's internal pressure.  PV/T=K explains it all.

There should be no difference--mechanical or otherwise--that will adversely affect the tank, regulator, or carbonation of the beer.  You may need to adjust the regulator due to the drop in temperature, but that's about it, and it should be expected.

Once the system is set up properly, the magic will happen.
Title: Re: Just bought a CO2 tank...
Post by: tygo on July 01, 2011, 03:01:28 AM
I've got my tank in the freezer out of necessity at this point and other than the sluggishness of the gauge, as mentioned above, I haven't had any problems at all with it.  And as far as the sluggishness goes it just requires a little patience which shouldn't be too hard to come by in this hobby  ;)
Title: Re: Just bought a CO2 tank...
Post by: oscarvan on July 01, 2011, 06:06:07 AM
I've noticed problems with regulators in the fridge, thanks for the explanation.  Can you put any numbers to how far off it is and in which direction?  Usually it just creeps up on me, and won't stay where I set it.  Do you know the recommended operation temp for most gauges?  My garage swings from 38-90+ over the course of the year.

Ah, my dear Sir, YOU need one of those little college fridges with a temp controller to keep your CO2 supply at a constant 70º..... ;D

Actually, more seriously now that I think about it....get a bigger fridge with a temp controller and a ceramic heat lamp, a DUAL stage controller and use it as a fermentation chamber AND keep your CO2 supply in there.
Title: Re: Just bought a CO2 tank...
Post by: Will's Swill on July 01, 2011, 11:49:26 PM
Count me as one who has operated my tanks both inside and outside of the keg cooler with no noticable effects on the regulator either way.