What's wrong with my system?

[BayouBrew]

Here's the problem. When I connect my regulator to the CO2 tank everything is fine for a little while, but then the pressure starts spiking (meaning that the pressure will rise until the relief valve releases over and over about once per second). I have tried 3 different regulators on two different tanks (one 5#, one 20#). I used to keep one of the tanks with regulator in the fridge and the regulator is a cheaper one, so I could see if that one was messed up. The other two have never been in a fridge, and one of them is a heavy duty Victor brand. Do you think that the tanks could be over filled and push liquid CO2 into the regulator? I got them both filled at the same time, so if their scale is off I guess that could explain both tanks causing the problem. The tanks have been kept upright when the regulator is attached, so that's not the problem either.

Any thoughts? I'm at a loss.

[Quin]

I guess you could confirm your theory by weighing the tanks (if you knew the tare weight). Or you could open the valve and bleed off some CO2 to see if it alleviates the problem.

[BayouBrew]

Yeah, I wish I knew the tare weight. I bled each tank for 1-2 minutes, but I don't know how long I would have to waste CO2 to remove a significant amount of liquid CO2.

[Grizz]

The tare weight will be stamped into the rounded edge near the valve at the top of the bottle. All bottles are stamped in the same general area. Some say tare before the numbers and some just have numbers. There is also the pressure certification dates there to. Was the bottle really warm when hooked up? Co2 is high temp sensitive if the bottle was too hot it would blow off or if it was over filled and slightly over warm it would. The regulator should blow off until the pressure is at a safe range. If it does not stop blowing off between 2000 and 1500 psi your regulators might need rebuilt.

[ajdelange]

If liquid CO2 were coming out through the valve (on the bottle) you would have seen dry ice forming. And you have tried this on 2 bottles. It is very unlikely that 2 bottles would be overfilled. This is a mystery for sure but at this point my best guess would be that beer had gotten into the regulator(s). Are there check valves installed?

[BayouBrew]

No beer in the regulator. Haven't even gotten beer in the lines.

[Charlie]

The fact that all three regulators did the same thing is pretty damn suspicious. I've never heard of a CO2 tank with a dip tube, but there are one or two things I don't know*. Do the dry ice guys use a dip tube?

*Google: http://www.cylindermart.com/co2.htm Medical and paintball cylinders use a dip tube. Maybe others do too. I betcha $1.00 that's the problem.

Charlie

[ajdelange]

Do the dry ice guys use a dip tube?
Charlie

Yes, they do, or at least the ones that make small quantities in the laboratory with devices like this one http://www.coleparmer.com/catalog/produ ... ku=0371600 connect them to syphon bottles. This is one of the reasons I'm pretty sure he doesn't have syphon bottles. If he did he'd see dry ice when he cracked the valve. If you've ever filled a bottle from a syphon you'll know what I'm referring to.