CO2 Tanks

CO2 tanks have at least three popular uses: 1. Presurizing Beer Kegerators. 2. Paintball cylinders refillers. 3. Air tank for tire inflation and power tools with off-road vehicles.
E.g. Power Tank: $350 at ExpeditionExchange, OffRoadAir: $230 at 4x4rockshop and Outback Air $290 at
Equivalent to most powerful compressors (see trip list).
Or you can get a tank on e-bay or for $85-100
and a regulator (Fixed 150 psi. $25-35, Variable 0-200 psi $85-125) (See: 4x4rockshop, Williams Balloons (800.235.4112).
20 ft or longer Polyurethane coiled air hose for $10-36 at:
Grainger > Pneumatics & Hydraulics > Air Compressor Accessories > Portable Air Tank Conversion Kits
Hose with guage $32 at Central 4 Wheel Harbor Freight Tools Auburn Blvd. and Garfield has hoses, regulators and connectors.
and bracket ($45).


  • Normal tank pressure is in the 700 PSI range. The pressure can fluctuate from 300 psi to well over 1,000 psi
  • The valve should have a pressure relief safety device. The device contains a frangible "burst disk" that is designed to rupture and safely release the CO2 contained in the tank should you accidentally overfill it or subject it to high temperature. The burst disc is uaually rated between 1,800 and 2,500psi for CO2 tanks and can be as high at 3,500 psi for Nitro tanks.
  • An overfilled CO2 tank, when subjected to summer time temperatures, will quickly build up enough pressure to blow out the 3000 PSI burst disc.
  • Tank should have a Hydrostatic test every 5 years. ($10-35).
  • Takes about 35 sec. to fill a tire from 15 psi to 32 psi. Faster than at gas station hose
  • Filling tank costs about $15-20
  • You will get about 20% pressure loss in a 20' coil hose.
  • 120 lbs. of pressure will inflate tires, run air tools and re-seat tires on the rim.
  • An air blow gun attachment will allow you to blow out dust from your interior and air filter.
  • Air tools run from 60 PSI to 90 PSI (typically), so you need a regulator to reduce pressure.
  • The pressure stays pretty much constant in the tank until it is empty, so gauges don't help much. You must weight the tank to see if it is getting empty.
  • See Safety rules below.

Power Tank Specs
Size * 5# 10# 15#
Total Height 21" (53cm) 24" (61cm) 30" (76cm)
Cylinder Diameter 5.2" (13cm) 6.9" (17cm) 6.9" (17cm)
Weight Empty 12 lb. (26.5 kg.) 17 lb. (37.4 kg.) 21 lb. (46.2 kg.)
Weight Full 17 lb. (37.4 kg.) 27 lb. (59.4 kg.) 36 lb. (79.2 kg.)
Pounds Liquid Cap. 5 10 15
Cubic Feet Cap. 42 84 126
Gallons Cap. 320 640 960
* 10# tank should hold 10#s of CO2
DOT approved tanks are typically rated to 3,000 psi.

Do it yourself instructions at:


Read this before connecting to CO2 tank
1. Always connect CO2 gas cylinder to reducing valve or regulator. Failure to do so could result in an explosion with possible death or inury when the cylinder valve is opened.
2. Never connect gas cylinder directly to keg.
3. Always secure gas cylinder in "upright" position.
4. Always keep gas cylinder away from heat.
5. Never drop or throw CO2 gas cylinder.
6. Always ventilate after CO2 leakage.
7. Always check the D.O.T. (Department of Transport) test date located on the neck of the cylinder before installation. If over five (5) years, do not use, return the gas cylinder to gas supplier.
8. Never connect a product container unless there are two (2) safety mechanism's in the pressure system
- One at or on the CO2 regulator. (the regulator supplied should be inclusive of such a safety mechanism)
- One at or on the product container coupler or in the pressure gas line. (the keg coupler should be inclusive of such a safety mechanism)
9. If it becomes difficult to breath and your head starts to ache, abnormal concentrations of carbon dioxide may be present in the area. Close the main valve on the CO2 cyclinder and leave the room immediately.
10. Gas cylinders should be stored in the coolest part of the establishment, preferably at 70° F., and securely fastened in the upright position before the primary regulator is attached to the cylinder.
Following a report of a defective CO2 tank exploding inside a motor vehicle, a nation-wide consumer safety alert has been issued regarding the "valve plug" on CO2 tanks. The valve plug (also called the "burst disk retaining nut") is the small brass, hexagon-shaped nut which is screwed into the valve assembly on the tank. It is supposed to have two small holes which allow for the release of CO2 should the burst disk rupture. The holes are supposed to be on opposite sides in the head of the plug. If the plug does not have these holes, your CO2 tank is not safe and should be returned to the manufacturer or place of purchase.

Bust disk installation:
10 Lb. New Steel CO2 Tank KE3c
Detailed Description

These brand new cylinders will give you years of service. We ship these cylinders empty, so you will need to have it filled before using (most welding shops or fire extinguisher service stations fill CO2 cylinders). The 10# cylinder will cost $10 to $20 to fill, and will dispense 12- 18 kegs. Our cylinders are guaranteed to have at least 4 years of service remaining before a required 5 year pressure test (this can be done by most CO2 filling stations). Regulator in picture is sold separately.

CO2 Regulators

by pH

The Question Was Asked:

> I have a CO2 emission system with no instructions and I was > wondering if you had any knowledge that would help me make the most of > this system. The regulator appears to be from a fire extinguisher > recharger. > The regulator brand name is Harris. The face of the regulator has #'s 10-60 > and says AR/CO2 and at the bottom of the regulator face it says > C.F.H.FLOW. The regulator runs into a Dayton time switch. > Any help would be greatly appreciated. Peace. There may be three gages and two regulators.

One gage would read the tank pressure only (very high psi numbers).

One gage would read psi from a regulator that controls the pressure coming from the tank (and going to the flow control). I believe this to be the "10-60 and says AR/CO2" you mention. I don't know what AR means.

The other would be a gage from the flow control that actually controls the amount of CO2 being released. Flow controls generally read in cubic feet (or liters) per hour (or minute), in your case the "C.F.H.FLOW" means cubic feet per hour. This would be calculated against the cubic footage of your room. Since flow controls work with lower pressures coming from the pressure regulator (in your case 10-60psi) that is usually where the solenoid connected to the timer is located (never hook the solenoid directly to the high pressures found in the tank).

The range of the flow control adjustment may be dependent on the psi setting of the pressure regulator. So if you can't get an adequate CO2 release for the timer you use, you may have to decrease psi. I'm hesitant to give info of this type because of the pressures approaching 1,000psi used in the CO2 tank. Pressures of that degree can be VERY dangerous if used with the wrong regulators, fittings, etc. (not to say yours are wrong). An explosion could take your head off, please keep that in mind. You may want to contact Harris for info, see if they got a web site. You never want to release CO2 directly from the tank, always use a proper regulator for CO2. Keep the tank upright during use, and use a small length of chain to keep it from falling over. I believe every 5 years tanks must be pressure tested for safety, the date is usually stamped on the tank. _______________________________________________________________________

Date: 7 Nov 1994 Newsgroup: rec.aquaria,alt.aquaria,sci.aquaria While waiting for my CO2 tank to be refilled at the local welding supply shop, I was browsing all the cool stuff related to the welding profession. Mixed in amongst the plaid caps and kinky leather face masks was a "FROG" - Flow Regulated Orifice Gauge. It is a preset regulator for CO2 tanks that is set to 22 PSI. It has a little button that either pops out or retracts when the tank is almost empty. This would be an inexpensive way to get setup with a more capable CO2 system. It was marked $22 and is made by Western (Model RP22320).

George Booth "Nothing in the world is more dangerous than than sincere ignorance and conscientious
Freshwater Plant Tank Technology stupidity" - Martin Luther King, Jr.

Frogs, Cables, Vacation

by George Booth
Date: Fri, 28 Apr 1995
> From: Erik Olson (e-mail)
> Date: Thu, 27 Apr 1995 19:36:22 -0700 (PDT)
> Subject: FROG

George, the FROG is a little better than that, because it does have a little pop-out thing that tells when the tank is running low. The label says "10 minutes left when it pops in". But this is for welders who are not running it through a needle valve, so I'd guess you probably have a week before you have to actually replace the tank.

A local store sells their own version fo CO2 injection using these FROG things and 5# bottles and they report that they have *never* seen the button do its thing. FWIW.

Regulated Flow Meter (for CO2)

by "John Y. Ching" Date: Thu, 3 Aug 1995 After buying a 15 lbs CO2 tank from a local fire extinguisher place, I have been searching for a good regulator and needle valve combination that's not too expensive. What I found was that any good two-stage dual gauged regulator used for welding cost anywhere between C$75 and C$160. I was also unable to find the fixed pressure FROG unit mentioned in the FAQ. I understand it doesn't have any gauge which is something I like to have. In terms of needle valves, the one George Booth recommended (Nupro B-4MG2) looked very solid but its C$59 cost is a bit expensive (why am I not surprised :-)). I also considered getting just a heavy duty valve, like the Parker valve suggested by Jamil Zainasheff, without the use of a regulator, but again I wanted to have something that had a gauge to tell me when the tank is about to go empty etc.

Finally I found a gaget called a Regulated Flow Meter which is essentially a regulator with an integrated needle valve control plus a flow rate gauge in units of CFH (Cubic ft per hour?). Although the flow rate gauge is not that useful for our purpose, I found that the integrated flow control is very smooth and precise. I can get exactly one bubble per second without doing much adjustment. It is rated for 3000 psi. There is also a round dial gauge that gives you the pressure (PSI) inside the tank. The whole thing is made of solid brass.

If you are interested, this thing is made by Victor Equipment Company of Denton Texas, model # HRF1425-580. I paid C$90 for it, cheaper than a good regulator+separate valve. And you don't have to look for different connector and hoses to connect the two. That's about US$65 at the current exchange rate. It may be cheaper in the States, especially if you have better welding contacts than I do.

John Y. Ching ( | Pattern Analysis and Machine Intelligence Lab | Department of Systems Design Engineering | University of Waterloo, Canada |

FROG valves

by (Dave Gomberg)
Date: Thu, 25 Jan 96
I talked to the FROG people and even got a data sheet. The FROG is NOT A PRESSURE REGULATOR, it is a FLOW REGULATOR (that is what the FR stands for). It is good in an application where it is the only component (other than the tank shutoff valve) and is used to deliver its rated value (8CFH as I recall). It is not good where a regulator is needed because if you put something after it intended to further reduce the flow, the pressure will just build up. Basically, a FROG is a pinhole, which thereby reduces the flow. If you need a regulator, you need a regulator, not a FROG. Dave

Dave Gomberg, Experimenta San Francisco CA USA


by George Booth
Date: Mon, 29 Jan 1996
> From: (Dave Gomberg)
Tyson, if you doubt what I say, try tank+FROG+gauge+needle-valve in that order and close the needle valve. The gauge will rise to 800PSI or so. CFM is not pressure, it is flow. The FROG is a Flow Regulator, not a pressure regulator. Flow and pressure are highly correlated, stop the flow and the pressure will go through the roof. Don't injure yourself, use proper equipment.

Dave, this setup is being sold by a local shop and works very well, no matter what the theory says.

> From: Erik Olson <(e-mail)>
Can normal needle valves withstand 800PSI of pressure directly? I read a post on here or rec.aquaria once of a guy who didn't use a regulator at all, but just hooked a needle valve directly to his CO2 bottle.

The Dupla "Starter Kit" I started with lo these many years ago had a needle valve that attached right to the CO2 bottle, a check valve, a plastic diffuser doodad and some silicone tubing. The needle valve did just fine "regulating" the 900 psi bottle pressure although it was a tad sensitive to adjust.

George Booth in Rather Chilly But Sunny Colorado

FROG update

by Tyson Lee
Date: Thu, 8 Feb 1996
Just as other had told me, this setup seems to be working just fine after a month or more in use. I used a 5lb. bottle with a FROG attached. From the FROG, I used some compression fittings for the tubing/needle valve connections. They leaked a bit, until I used more teflon tape. They do not leak a bit now.

The only problem I had, was the temperature sensitivity of the needle valve. The rate would fluctuate highly depending on the ambient temperature. Once the central was working again, this has become very minimal.

I had the tank refilled after it had emptied in about 3 1/2 weeks. (bubbling was way too inefficient) I have since tried to bubble it into some bells at a much slower rate. I should at least get about 6 weeks out of this refill and more once I get this rate all figured out. In the end, it cost me about $90.00 for the whole setup.

I simply wanted to let Eric(cause he had asked how it was doing) and others know that it _is_ working fine despite warnings about having my hand blown off. It sure beats the hell outta mixing that yeast. Then again, I still mix it for my other tanks.

Up too late again,

CO2 regulator valve

by "Dave Gomberg"
Date: Sat, 20 Jul 96
Found a great vendor. Amber Waves Brewing Supplies 2808 LaVista Road, Decatur GA 30033, 404-315-1100

$35 for a custom rebuilt regulator, ask them for 0-10PSI spring and 2nd stage gauge. It will then be possible to reduce the pressure to a low enough value to use regular air hose and valves for the rest of the project, just like with an air pump. No need for a special needle valve.

Dave Gomberg, Experimenta San Francisco CA USA


Bottles and Tanks ata AeroCon
20 oz. tank

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last updated 22 June 2004