Guest Posted March 22, 2011 Share Posted March 22, 2011 I am stumped on this one so thought I would ask here and maybe someone might be able to help. I have a leak in a keg I put in sometime ago. It is only very small but it is obvious it is coming through the Pressure Relief Valve (PRV). Now to provide a quick fix I changed the whole lid but only to find the next one is leaking as well. So what do I do now?... I changed to another lid and guess what?.... yep, it also leaks. Now the wierd thing is that these lids/PRVs are fine and do not leak when they were on a different keg. Is it possible to "overfill" the keg which could result in this type of problem? Link to comment Share on other sites More sharing options...
craigb12 Posted March 22, 2011 Share Posted March 22, 2011 I'm pretty new to kegging (so someone else might be better placed to answer this question) but i've had similar problems with some of my kegs. I've found that they don't form perfect seals at very low pressures (say, 2psi) but when the pressure is increased (say, above 10psi) the seal is secured. This is, obviously, because pressure is needed to force the lid closed, and to to make a good seal with the O-ring. But i don't think this should affect the pressure release valve all that much. I do have two or three lids whose PRVs are a bit temperamental. I don't really have a perfect solution, but sometimes I find that if i take them off and put them back on again (sort of like re-starting a computer) it can seal the leak in the release valve. Also, I sometimes find that when i can hear the leak fizzing out of the PRV, if i twist the ring on the valve (maybe by only a few degrees) there is an audible difference in the pressure being leaked - and there's often a 'sweet spot' where it stops leaking altogether. Like I say, i'm no expert on kegging, and someone with a bit more experience might be able to give you a much better response. One slight silver lining is that, even with your leak, assuming that it is quite small, it is unlikely that the beer you've kegged will become spoiled. The pressure on the inside of the tank should quite easily remain greater than that on the outside of the tank, and it's fairly unlikely that any oxygen should get in and cause the beer to go stale. Craig Link to comment Share on other sites More sharing options...
PB2 Posted March 22, 2011 Share Posted March 22, 2011 Do you have a photo of the valves that you can post on here? Some relief valves can be old and dodgy. I haven't seen replacement seal kits for relief valves so I guess the fix would be to replace the complete unit. Are you testing by using soapy water or is the leak more obvious than that? I guess over-filling would be to the point that there is no headspace?? My kegs have a very short tube protruding into the headspace from the gas post. I fill to about an inch short of that. Craig, the over-centre latch on the lid should create enough pressure, in combination with the oring, to seal. If you don't get a good seal in the lid you may need a new oring... Link to comment Share on other sites More sharing options...
Guest Posted March 22, 2011 Author Share Posted March 22, 2011 Do you have a photo of the valves that you can post on here? Some relief valves can be old and dodgy. I haven't seen replacement seal kits for relief valves so I guess the fix would be to replace the complete unit. Are you testing by using soapy water or is the leak more obvious than that? I guess over-filling would be to the point that there is no headspace?? My kegs have a very short tube protruding into the headspace from the gas post. I fill to about an inch short of that. Craig, the over-centre latch on the lid should create enough pressure, in combination with the oring, to seal. If you don't get a good seal in the lid you may need a new oring... I will take some pics tonight. (I'm at work now) I could replace the complete unit but as I posted, I switched over 3 lids, which were working fine on other kegs. The first one I tested using starsan which worked fine but the other 2 I could hear it leaking and when I shook the keg a little, it confirmed it. I actually filled this particular keg just over the weld line and I feel it has plenty of headspace, am guessing at around 2 inches. Hey Paul.... I appologize in advance. I seem to be coming up with all the hard ones lately.[alien] Link to comment Share on other sites More sharing options...
Guest Posted March 22, 2011 Author Share Posted March 22, 2011 Here are the lids I used. 2 has an older type PRV and 1 has a newer one. I have now changed it again and replaced with the ring pull one and smothered it with lube. So far it appears to be ok but will know for sure in the morning. Edit: No still leaking as of this morning. Link to comment Share on other sites More sharing options...
PB2 Posted March 23, 2011 Share Posted March 23, 2011 Snap! I have the very same as the two on the left of your pic [biggrin] Had mine since 2000 and never had an issue. Did you do the soapy water check to be absolutely sure the leak is out of the valve and not the seal around the latch? Is there a chance that grit, perhaps the sodium percarbonate in Coopers Sanitiser, has become lodged in the valve seat? Might be able to clear it by holding the valve open and rinsing hot water through it. Link to comment Share on other sites More sharing options...
Guest Posted March 23, 2011 Author Share Posted March 23, 2011 I remove all the valves and clean and rinse when I clean the kegs. I have rinsed these several times since the leaks were identified but only when removed from the lid and they still leaked. I will rinse again tonight with the valve open and see what happens. Failing this, I have another 6 lids I can try and if that doesn't work, I have a brand new 23L keg that has only been used once. I will use the lid that has and see what happens. Surely all these wont have the same problem one would think. I check for leaks with starsan which usually shows up when there is one. Link to comment Share on other sites More sharing options...
Guest Posted March 24, 2011 Author Share Posted March 24, 2011 I removed the valves again on the above 3 lids and ran hot water through them then sprayed with starsan and replaced. However, they all still leaked. I filled another keg last night and tried these lids on that as well but with the same result. Therefore, I have no changed the 2 over with 2 others I had from some 9L cornys I got recently. Left gas on last night at 300kpa and turned it off this morning. I will check when I get home to see if the pressure holds. Does anyone know if there are any cleaning chemicals that might cause this problem?... All 3 lids/PRVs were working fine until I soaked them in a keg cleaner chemical. I haven't seen an O-ring for these but my LHBS has an o-ring for relief valves for .60c. Maybe I might have a talk to them about it. Link to comment Share on other sites More sharing options...
Matty A Posted March 24, 2011 Share Posted March 24, 2011 I think that you should take the keg (with the lids) that is the culprite to the LHBS. Have him have a look at them and he might be able to better diagnose the issue. It sounds like it is an issue with the keg but I can't be sure. It might be as simple as replacing the o-ring. Link to comment Share on other sites More sharing options...
Guest Posted March 24, 2011 Author Share Posted March 24, 2011 I think that you should take the keg (with the lids) that is the culprite to the LHBS. Have him have a look at them and he might be able to better diagnose the issue. It sounds like it is an issue with the keg but I can't be sure. It might be as simple as replacing the o-ring. My problem right now is that these kegs are full so I can't really take them in. I have sent the LHBS an email and if what they have are o-rings for PRV's then I'll get 6 or so and change them over. Other than this I'll take them in. I didn't think of that.... doh! Be buggard if I knew there was an o-ring in them though. I guess there would have to be. No doubt it would be a pain in the bum to change. Link to comment Share on other sites More sharing options...
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