Which of these is the hydrostatic test date of my 5# soda CO2 tank?

[Danny D.]

Which of the myriad numbers on my tank is the hydro date?

I have this 5 pound carbon dioxide tank for making soda:

I bought the original from Praxair, who replaced my brand new C02 tank with a cruddy one, and then swapped it out continually:

I've been swapping out the tank for years, but lately, they don't have the 5-pound C02 tanks size in stock. They say their supplier doesn't have the "steel" (which is their nickname for empty tanks to fill).

This lack of "steel" has been going on for weeks.

So, today, I called up the other two local suppliers:

1. Praxair 408-588-2035 .49 for a swap of steel for steel
2. Airgas 408-998-63.90 for a swap of steel for steel
3. Carbonic 408-727-8835 for a refill of steel

For the first two, I can swap out the Praxair tank and they will take it, even if it is past its 5-year hydro test point (which is how Praxair talked me into swapping out my brand new tank for their beat up ones all the time in the first place).

But, Carbonic (naturally) won't fill it if it's past its five year hydro date.

Question is: hhhhhhhhhhh TW10.3V

10M80

7X56

[Carl Ijames]

The TW10.3 is the tare weight, the weight of the tank empty, 10.3 lbs. My guess is that the 7X56 is the original hydro date (July, 1956) based on its position under the other numbers, and the 10M80 is from a retest in October,

1975.

Which of the myriad numbers on my tank is the hydro date?

I have this 5 pound carbon dioxide tank for making soda:

I bought the original from Praxair, who replaced my brand new C02 tank with a cruddy one, and then swapped it out continually:

I've been swapping out the tank for years, but lately, they don't have the 5-pound C02 tanks size in stock. They say their supplier doesn't have the "steel" (which is their nickname for empty tanks to fill).

This lack of "steel" has been going on for weeks.

So, today, I called up the other two local suppliers:

1. Praxair 408-588-2035 .49 for a swap of steel for steel
2. Airgas 408-998-63.90 for a swap of steel for steel
3. Carbonic 408-727-8835 for a refill of steel

For the first two, I can swap out the Praxair tank and they will take it, even if it is past its 5-year hydro test point (which is how Praxair talked me into swapping out my brand new tank for their beat up ones all the time in the first place).

But, Carbonic (naturally) won't fill it if it's past its five year hydro date.

Question is: hhhhhhhhhhh

TW10.3V

10M80

7X56

[Danny D.]

Carl Ijames wrote, on Wed, 24 Sep 2014 19:07:12 -0400:

That's great information! TW10.3 ? tare weight of 10.3 pounds

7X56 ? original hydro tested date (1951 to 1956) 10M80 ? October 1975 hydro tested date (10/75 to 10/80)

Since the tank was given to me by Praxair in exchange for mine, it must have a *later* date on it somewhere, or they wouldn't have given it to me (one would think).

Looking at *all* the numbers:h

ICC 3AA1800 is just below the neck

5-59348 is just below that GPAC is below that 756 is below that

TW10.3 is on the opposite side of all those original numbers

K0 is high up on the neck

8L66 is just below that 10M80 was apparently added later

And then, there are these cryptic numbers:

708 UE

Do you think that means July 2008? If so, how did they give me the tank if that date is far past?

I've had the tank about a year or so, I think.

[Pico Rico]

yes, I think this means it was tested in July 2008

or so? maybe you got it within 5 years. or, "close enough".

[Danny D.]

Pico Rico wrote, on Wed, 24 Sep 2014 17:36:21 -0700:

Maybe. I don't really remember, as I haven't made soda in a while, and when I looked, it was empty (from me not shutting it fully off most likely).

Anyway, in hind sight, if anyone here asks whether it's better to own them or to just trade them in, I'd say now that it's better to own them, even though Praxair talked me out of that when I first returned mine.

Anyway, if it is 2008, I'm stuck waiting for Praxair to get "steel", since they would replace it with one within the 5-year period.

[Danny D.]

Pico Rico wrote, on Wed, 24 Sep 2014 17:36:21 -0700:

I wonder how much a "stamp" costs so I can stamp something like today's date on it? :)

BTW, does that mean the stamp is the END date or the date TESTED? We have two different interpretations in this thread.

[Pico Rico]

The tested date.

[Danny D.]

Pico Rico wrote, on Wed, 24 Sep 2014 18:27:22 -0700:

Thanks.

So it has been tested 4 times:

756 ? test date July 1956 (where the is the tester's mark) 8L66 ? test date August 1966 (where the L is the tester's mark) 10M80 ? test date October 1980 (where the M is the tester's mark) 708 UE ? test date July 2008 (expired July 2013)

Googling, I find this for the rest of the numbers:

ICC 3AA 1800 ? ICC agency, 3AA steel, 1800 psi TW10.3 ? tare weight of 10.3 pounds

5-59348 ? serial number GPAC ? manufacturer K0 ? ?

[Carl Ijames]

First, I misspoke as another poster pointed out, the date is the date of test not expiration. Second, yes, I think the 7 08 is the latest test date, July 2008. The ICC 3AA specifies the type of tank and how often it must be tested, and the 1800 is the maximum use pressure, 1800 psig. I forget what the next two lines mean. I was told once that the symbols between the month and year on the hydro test identify the place that did the test but I have never verified that; could be the test procedure or something else. If you are really in a hurry, maybe you can go back to Praxair and swap your empty for another empty with a current hydro test date?

----- Regards, Carl Ijames

Carl Ijames wrote, on Wed, 24 Sep 2014 19:07:12 -0400:

That's great information! TW10.3 ? tare weight of 10.3 pounds

7X56 ? original hydro tested date (1951 to 1956) 10M80 ? October 1975 hydro tested date (10/75 to 10/80)

Since the tank was given to me by Praxair in exchange for mine, it must have a *later* date on it somewhere, or they wouldn't have given it to me (one would think).

Looking at *all* the numbers:h

ICC 3AA1800 is just below the neck

5-59348 is just below that GPAC is below that 756 is below that

TW10.3 is on the opposite side of all those original numbers

K0 is high up on the neck

8L66 is just below that 10M80 was apparently added later

And then, there are these cryptic numbers:

708 UE

Do you think that means July 2008? If so, how did they give me the tank if that date is far past?

I've had the tank about a year or so, I think.

[Danny D.]

Carl Ijames wrote, on Wed, 24 Sep 2014 21:57:35 -0400:

That's an interesting idea! I hadn't thought of that. But I don't think it will matter.

What I *want* is carbon dioxide, not an empty tank (I already have an empty tank).

When I bought the brand-new tank, Praxair talked me into swapping it for their tanks based on the fact I'd never have to hydro it.

At the time, I hadn't known that Carbonic, literally across the street, will refill the tank for 2/3 of what Praxair charges.

So, in reality, it was false economy to let let Praxair do the hydro, because had the tank been within the 5 years, it would have been filled by now.

As it is, I'm forced to *wait* for Praxair to have steel in stock.

[Carl Ijames]

I meant, get a tank from Praxair and take it to Carbonic and pay them to fill it. Then decide if you ever want to go back to Praxair (maybe just before that hydro expires? :-)).

Carl Ijames wrote, on Wed, 24 Sep 2014 21:57:35 -0400:

That's an interesting idea! I hadn't thought of that. But I don't think it will matter.

What I *want* is carbon dioxide, not an empty tank (I already have an empty tank).

When I bought the brand-new tank, Praxair talked me into swapping it for their tanks based on the fact I'd never have to hydro it.

At the time, I hadn't known that Carbonic, literally across the street, will refill the tank for 2/3 of what Praxair charges.

So, in reality, it was false economy to let let Praxair do the hydro, because had the tank been within the 5 years, it would have been filled by now.

As it is, I'm forced to *wait* for Praxair to have steel in stock.

[Tom Miller]

What ever you do, don't stamp a fake date on the tank.

[Danny D.]

Carl Ijames wrote, on Thu, 25 Sep 2014 12:06:03 -0400:

Oh. I'm sorry. That *is* clever!

It solves *both* problems.

I will call Praxair now. Praxair 408-588-2035 $29.49 for a swap of steel for steel