Grades of CO2

singleshot · Post by **singleshot** » Fri Dec 19, 2008 6:43 am

I have purchased a Steyr LP1.

Is it essential to use "food grade" co2?

I have a co2 fire extinguiser that my adapter will fit.

Any help would be great.

Cameron

TB · Post by TB » Fri Dec 19, 2008 7:36 am

When I had a CO2 LP1 years ago, I used an old fire extinguiser to fill up my cylenders without any problems!

Maybe you know this, but you can get a kit for changing from CO2 to compresed air. It includes one air cylender a filling adapter and a new valve. The kit goes for about €200.

Richard H · Post by **Richard H** » Fri Dec 19, 2008 8:01 am

I could be wrong but bulk CO2 is bulk CO2 the food grade part has more to do with the container that it is dispensed into ie. Stainless steel containers. Fire extinguisher and welding supply sources are fine the big thing to remember is that your tank needs a dip tube to ensure that you get liquid not gas.

LesJ · Post by **LesJ** » Fri Dec 19, 2008 8:54 am

Richard H wrote:I could be wrong but bulk CO2 is bulk CO2 the food grade part has more to do with the container that it is dispensed into ie. Stainless steel containers. Fire extinguisher and welding supply sources are fine the big thing to remember is that your tank needs a dip tube to ensure that you get liquid not gas.

Small tanks with out the tube can still be used, all you have to do is to hold tank up side down from when you open the valve till it is filled and vave is closed, which takes few secends.

Gwhite · Post by **Gwhite** » Fri Dec 19, 2008 2:56 pm

The main thing you want to be careful about is the cylinder you get. A friend of mine got a "great" deal on a used soda carbonation cylinder. What he didn't find out until it was too late was that someone had managed to back fill it with several cups of water. This is apparently fairly easy to do in a multi-cylinder setup if they run a cylinder until it is completely empty, and then leave the valve open when they re-pressurize things.

The end result is an extremely expensive water pistol. I always used laboratory/industrial CO2 because it is supposed to be drier than food grade, where they don't care about moisture. I would think they wouldn't care about water in the CO2 for fire extinguishers either, so moisture could be an issue.

singleshot · Post by **singleshot** » Fri Dec 19, 2008 10:27 pm

Thanks for the help.

I have tried co2 from the extinguisher this morning with no problems. The only thing was I could not fill to the max weight for some reason.

Water should not be a problem as co2 extinguishers are designed for electrical fires where water is a no no.

Regards
Cameron

LesJ · Post by **LesJ** » Fri Dec 19, 2008 10:59 pm

In warm weather it is hard to fill to the max. You will need to chill your cylinder in a freezer or partialy charged with co2 and than quickly discharge it. That will chill it quickly. In a freezer you need to keep it for 15 min. or so.
In cold weather it is very easyly to over fill. You need some space for liquid to expand or cylinder or valve will burst.
Safest way is to weight the charge. Tara and charge weights are printed on the cylinders.