I built my own kegerator out of a full-size fridge. I have tested all the connections with soapy water and I am getting no bubbling. There is a very slight hissing coming from the CO2 tank. I have looked into this and most people have said is the safety valve or it's a diaphragm issue inside the regulator. Does anyone else have any input?
I have heard tell of the rubber gasket on the regulator connection wearing with time so that might be worth checking. See part 12 here on the exploded diagram PDF: http://www.taprite.com/3741-br-3741-br I have personally had to tighten the nut on the regulator connection to the tank as well. That would be part 10 on the diagram. If the leak is truly on the tank, I'll let some of the more experienced forum members weigh in.
Are you certain you aren't hearing gas entering the keg? If there is a constant hiss, it is a leak. You'll be empty in a day. Check to be sure you have the plastic washer in the nut that connects to the tank. It may also be made of felt. And in some cases there is an integral o-ring fixed in place. If you don't have any washer then that's your leak. 9 times out of 10 that is the leak source. Also, crank down on the connecting nut until it wont turn anymore. Don't be afraid to really tighten it up. Gas exits the tank around 800 psi, so you really want the threads to be mated tight. If your Pressure Release Valve is leaking it can sometimes be replaced. Depends. Some of them are built in, others screw on to the regulator body. I yours screws on then tighten it. You can always check the PRV status by turning the regulator wide open. The PRV will begin to release at around 55 psi and be screaming gas at 60 psi. If your valve is leaking at say, 20 psi, it needs to be replaced. If this is a no name $20 regulator, throw it out. Buy name brand . Cheers.
No need to overdo it. It's easy to damage the nylon gasket by overtightening, creating a leak where there was none, and, in the case of an o-ring, once it's fully compressed to the point that the brass parts are touching, you've achieved all the seal you're going to get. Also, since the threads don't seal anything here, there's no need for them to be 'mated tight', though I may have misinterpreted your meaning there. Turn up the pressure to 50 psi or so to see if you can tell where the hissing is coming from. Spray some StarSan solution or soapy water on every connection in the area of the sound. Unless it's gas entering the keg, as billandsuz suggested (my first thought, actually), it should be visible.
I believe when I had a slow leak I had tried a few things to isolate the leak. With the CO2 on shutoff the CO2 to the Keg. Then turn off the CO2 and let it sit overnight. If the gauge on the CO2 stays steady at your CO2 setting then turn the CO2 back on to the keg. Let it sit overnight and see if your gauge stays steady. That will determine if its before or after the keg shutoff (e.g. whether your hose connections are good or not or if its somewhere in the regulator or the connection to the CO2). Once you determine where the leak is douse everything with the soapy water, including the whole top of the CO2 bottle. Something's got to bubble if you have a leak. The bottle could be the source of the leak as well. It took me a while to find my leak but by isolating the CO2 by turning off both the bottle and the connection to the keg it allowed me to know when I truly fixed the leak.
