I'm having trouble locating tips on finding an ellusive CO2 leak, so I thought I would start a thread.
I built my keezer in the summer of 2011, and my first 5 lb bottle of CO2 lasted over a year. My second lasted about 6 weeks, which was quite a surprise. I immediately suspected the bottle (I don't really have anywhere to get bottles refilled, so I have to swap bottles when I need a refill) and/or the plastic washer. I talked to the bottled gas guy, and said that it's pretty rare for a bottle to leak, and he also said that the washers usually last longer than one bottle, but they're cheap so I replaced it when I traded.
After installing the third bottle, I ran a few simple troubleshooting tests ... each time, I pressurized the system and then shut the main valve on the bottle and waited to see if it would hold pressure ... it didn't.
Since then, I've just been closing the bottle valve in between uses until I had a chance to take the keezer offline for closer analysis and repairs ... and that time came this week, when both kegs finally became empty at the same time.
I unhooked and removed the kegs, closed the valves on the distribution header, unplugged the controller, and let everything come to room temperature. I pressurized it and then shut the valve on the bottle. I just checked it, now 5.5 hrs later, and the secondary pressure has dropped from 11psi to 9psi ... not as bad as I had expected, I guess, but still a leak.
I bought the system pre-assembled. The CO2 hose is clamped onto the regulator with a crimp clamp. The other end of that 4' hose is secured with a worm gear clamp to the fitting that is threaded into the header. Unless the valves are not completely sealing (possible, but probably not the problem, since the leak existed when the kegs were connected also), my leak must be in those few joints, right?
What I'm having trouble imagining is how a change in bottles would have affected any of those joints. I'm not tough on the hardware. And I replaced the plastic washer between the bottle and the regulator, which was the most obvious (or so I thought) culprit.
Thanks for any tips you might have.