My CO2 bottle ....

[MT2sum]

I used to be an appliance serviceman and was able to buy used equipment sometimes. I still have a CO2 bottle/tank that I got about 20-25 years ago, along with a "carbonator pump" and a Coke syrup machine. I sold the Coke machine to a collector, but he didn't want the carbonator pump or the CO2 bottle/tank. The CO2 bottle/tank still has pressure on it and I've bought new gauges for the old regulator .... but I'm wondering if I need to get the tank 'pressure checked' and also if the CO2 would be any good after all these years. (I'm a bottler, not a kegger). I also have a few used 5 gallon kegs, so my thought was to do some research on using the kegs for fermenting in and then use the gas to transfer from one to another, so I could use a beer gun to bottle my brews. There are several beer guns out there, plus, I have seen one or two DIY versions on the internet. Eventually, my plan is to have a keggerator, but that's a long ways off!

I'm not sure whether a carbonator pump is useful nowadays, but if it is, I might could use it for making soda pop for the grandkids if I can find/figure out how it works.

Any help, advice, etc. would be appreciated!

 

[IslandLizard]

Rust inside could be an issue for the quality of the CO2. Who knows, maybe it's just fine.

The hydro test is valid for 5 years, so it definitely needs to get retested on your next fill. Such a test runs $20-35 (or more), regardless of pass or fail. The tank will be emptied and inspected before they can hydro test it.

Best option: When it goes empty, find a place that swaps tanks without looking to closely at the tank. Call around.

 

[MT2sum]

Yeah, swapping tanks sounds like the better idea! I don't like the sound of 'possible' rust inside ;>)! Since I have no idea about whether or not there's rust, I think I'd be better off just blowing off the pressure and forget whatever is inside. It feels like it's full, but until I get the new gauges onto the regulator, it'd be a guessing game anyways!

 

[day_trippr]

I would think it'd be difficult to develop rust inside a cylinder that's been used steadily for CO2 and still has gas remaining within. In any case, as described, no gas outlet is going to fill that cylinder without a hydro test, so a swap - especially if it doesn't cost extra - is inevitably the way to go.

The local AirGas filling station has been very good about simply taking in expired cylinders in trade without charging for a test (which can run $25 or more) and others have had similar experiences with AirGas in that regard...

Cheers!

 

[IslandLizard]

I'd bubble some CO2 through some clean water and see if you detect any coloring or off aroma/flavors. It's probably just fine.

I mentioned rust as a possibility, depending on the tank's history. The tank should be safe to use as is. It's just the regulations on refilling wants them to be recertified.

 

[MT2sum]

I'd bubble some CO2 through some clean water and see if you detect any coloring or off aroma/flavors. It's probably just fine.

I mentioned rust as a possibility, depending on the tank's history. The tank should be safe to use as is. It's just the regulations on refilling wants them to be recertified.

I just spent some time on the phone today talking to a welding supply about 2 hours away, and the person on the other end told me that CO2 has no moisture in it, so he wouldn't suspect any rust - that being said, I think your idea of running a hose from the regulator to a bowl of water is a good idea, ...... just to check ;>);
They don't swap tanks, so it looks like I'll have to pay the $35-$40 for a pressure test, but he also told me that CO2 doesn't break down, so no matter how long it's been in the tank under pressure, it'll be OK! I described it to him - it's a steel tank, and most likely a 20# tank, so when I look around at what they cost, they're anywhere from $125-$150 and up ..... I'm sure glad that I hung onto it all these years !!

 

[IslandLizard]

I just spent some time on the phone today talking to a welding supply about 2 hours away, and the person on the other end told me that CO2 has no moisture in it, so he wouldn't suspect any rust - that being said, I think your idea of running a hose from the regulator to a bowl of water is a good idea, ...... just to check ;>);
They don't swap tanks, so it looks like I'll have to pay the $35-$40 for a pressure test, but he also told me that CO2 doesn't break down, so no matter how long it's been in the tank under pressure, it'll be OK! I described it to him - it's a steel tank, and most likely a 20# tank, so when I look around at what they cost, they're anywhere from $125-$150 and up ..... I'm sure glad that I hung onto it all these years !!

Call around a bit more. $40 sounds steep.
Fire protection services that fill on premises often do hydro tests. One of such place here does them for $25. They get filled with water for the test, then dried. If they're not totally dry or the water in the tank is especially scummy, and they don't get rinsed out, that can become a source of contamination, IMO.

The Praxair outfit I got my last (out of date) tank swapped at did not charge me for a hydro test, because the (aluminum) tank "looked good and was fairly new." He said people bring in old rusty clunkers from before the millennium, so they will charge for the test on those.

If you can get it swapped at some point for something a bit more recent, all the better, I'd say. But tanks should last a long time if not physically damaged, like dropped from a truck.

I still use the Yellow Pages (paper edition) to find resources for many things. Not every hidden gem is easy to find on the net.

 

[IslandLizard]

On another note, I also have an beautiful shiny aluminum 15# tank I bought off CraigsList, including a double regulator. I had it refilled a couple times, but I found out when it expired, 15# is not a general swapping size, so I need to get that thing tested some day.

Some outfit on here is selling "reconditioned" 15# aluminum tanks for $60. Just in case, beware of the uncommon size. 5, 10, 20, 50# are the most common.

 

[firerat]

The local AirGas filling station has been very good about simply taking in expired cylinders in trade without charging for a test (which can run $25 or more) and others have had similar experiences with AirGas in that regard...

Cheers!

I can vouch for Airgas being great about taking old tanks for swaps. I've actually done it a few times with some ancient rusted old tanks with no problems at all.