CO2 Pressure Won’t Stop Increasing

[BryanEBIAB]

Hey folks,

Been kegging with the same system for years and something weird just started happening. When I swap CO2 tanks, I always do the following:
1. Turn all valves off and turn pressure as low as possible.
2. Replace tank
3. Open valve in tank

At this point, the new odd behavior begins: the needle starts increasing quickly. Within a couple seconds, it’s pinned at the max.

4. open the shutoff valve.

At this point, the needle drops back down to zero.

5. slowly turn up the pressure to about 5psi

Except it doesn’t stop. It *slowly* creeps up to 15+ or more after a few hours (maybe less). I back it down to zero, bleed off, and slowly increase to 5 psi again. But the cycle repeats—until I’m out of gas again!

I’ve got an edgestar kegerator and I’m using the regulator that came with it. Is this fixable or is it time to toss this regulator?

Thanks in advance!

 

[day_trippr]

Two possibilities: there is a bit of crud inside the regulator body preventing its tiny needle valve to seal; or that needle valve assembly (usually a cartridge) needs replacement.
For the former, you can try this:
- close the cylinder valve, remove any hoses from the regulator, and fully open its shut-off valve.
- turn the regulator pressure knob up a good couple of turns like you want a very high pressure.
- now, get a good grip on the cylinder/regulator assembly, and point the regulator output in a harmless direction.
- then, open the cylinder valve to cause a short but solid blast of CO2 out the regulator. Do that a couple of times.
- dial the pressure knob all the way back down and close the regulator shut-off valve.
- at this point you should be able to test the regulator: open the cylinder valve and slowly dial up the pressure to, say, 11 psi, let everything sit, and see what happens...

Cheers!

 

[BryanEBIAB]

Thanks, Day_Trippr! I tried the method you describe but unfortunately it didn’t help. I took the plunge and took it apart. I discovered *a lot* of crud in there that might have been causing the issue you mention. Looks like some moisture got in there at one point and corroded one of the springs. The spring is thick and seems okay but metal shards and dusty corrosion was all over the place! I did my best to clean it out. I kept going as per this video:


I got down to the piston and o-ring. I gave everything a good wipe down with a clean rag and lubed with keg grease (hope that’s okay!). I also added Teflon tape to the threads of the nut that hold the piston (like the video describes).

I put everything back together and so far so good! Holding steady at 5psi for the last hour!

I think it would be best to replace the whole unit due to the corrosion and maybe put this one to use force-carbing kegs in storage. Good learning experience and I’m happy to be back in business for the time being.

 

[day_trippr]

Kudos on breaking down your regulator - even though they are amazingly simple and easy to disassemble devices they do tend to scare folks from doing basic work on them.

The creep thing is a classic symptom of the regulator valve "failure to close tight", so I do believe that crud was getting caught up in the tiny mechanism that actually controls the gas flow. Hopefully your thorough cleaning and lubrication will have set it right.

Cheers!