Kegging Setup CO2 leak - driving me insane

[DJ_L3ThAL]

I appear to have a small leak as I lost most (~1-1.5kg) of my 2.6kg CO2 fresh bottle just before Xmas when I carbed one keg at 3bar for 24 hours. The beer was carbed as expected so then I set back to my serving pressure of 1bar on all 3 kegs.

I normally turn off the bottle after use, so I was finding when I came to use the system the regulator would read slightly lower than 1bar and when opening the bottle valve it would squirt gas into the kegs. I thought it might be the keg lids or post seals as I have some new 2nd hand kegs which I didn't replace all seals, but over about 3-4 uses since Xmas the bottle has no liquid left and just gas.

Did a quick leak test with starsan on all connections and couldn't detect any.

I took it to my LHBS thinking perhaps something could be wrong with the bottle as there is some loose metal inside when I turn it upside down, not sure if the keg king bottles have a float spring type non return valve which may be busted? Although that wouldn't cause leaking outwards... Was told to take bottle home to use remaining gas to keep keg headspace gassed as he didn't have any full bottles left, he's happy to take the bottle to KK for checking for faults later this week.

I thought I'd do a thorough leak test (all at 3 bar pressure) in the interim and have gotten to the end of my tether as I've worked backwards through the system removing branches on disconnects, check valve, ball valves and sections of line. It's gone back to being a barbed hose off the regulator (KK MKII) to a barbed metal nipple into a KK plastic gas splitter. I've got three of these splitters and each one on the end still leaks the same.

A full underwater test of EVERYTHING including bottle and reg didn't reveal any obvious leaks (in fact the air inside the gauges bubbled out as soon as I put it under but I left it all underwater for over an hour to let it settle and still nothing was apparent). Have crimped clamps on barbs even tighter, even thread sealed both threads on the regulator outlet nipple with Teflon tape. Haven't tried the gauge threads or the thread on the regulator type30 outlet steam as the bottle is now empty from my tests.

My main question is, can the cheaper beer/gas line from keg king permeate CO2 out slowly? Or could the CO2 bottle itself be faulty and have a small enough leaks to go undetected but slowly let pressure out over time? The high pressure gauge did seem to consistently drop since I got this bottle and I've reseated the type30 bottle connection multiple times in the interim.

Sorry for the essay, hopefully I've detailed it enough that someone can see something obvious from similar experience!

I can post pics of the system if it would help?

 

[DU99]

i was losing co2 at a very slow rate, found out the washer between the bottle and the reg wasn't seating properly.

 

[DJ_L3ThAL]

Thanks for the reply mate, I've got check valves in my system though, so wouldn't explain the loss of pressure downstream of those would it? I've tightened the bottle connection up to the point that I'll need a new washer for the next bottle anyway though lol, also sprayed soapy solution all around that and could not detect any bubbles even tiny ones? So I can inspect, was there visible damage to the washer or a split? Or did you just swap it and then found no more leaks? I'm reluctant to buy another full bottle until I know there are no leaks :S

Side note: Where can you get those washer replacements? I don't see them in the KK catalogue?

 

[Dae Tripper]

Just because you have check valves doest mean it won't be leaking downstream. They are simply one way valves. Have you water tested the kegs? Do this with the dissconects on as you may get a leak there as well.

 

[GalBrew]

The KK plastic gas splitters are not that great. I used to run 4 joined together and it was constantly leaking. I now run a KK 6-way manifold with no issues.

 

[DU99]

i get my washer's from Supagas..they give me a packet when i last got my co2 bottle filled..the washer wasn't sealing properly.noticed is was very thin and out of shape.

 

[DJ_L3ThAL]

Just because you have check valves doest mean it won't be leaking downstream. They are simply one way valves. Have you water tested the kegs? Do this with the dissconects on as you may get a leak there as well.

Yes, it would. As the regulator up to the check valve would drop in pressure, but the higher pressure downstream cannot equalise through the check valve, so kegs would remain at the same original pressure. So when I was turning the system on and getting flow which I could hear I to the kegs themselves it indicated a leak downstream. But the plot thickens as below...

What doesn't make sense is that I've tested the system with simply the bottle-regulator-line-1xsplitter with the valve closed and both ports blocked and it still leaks. So whether the kegs or disconnects/posts are leaking is another story as I'd like to be confident the bottle, regulator and gas line are all not leaking before testing further downstream as they at this stage are not the root cause given they've been removed from the system and the leak persists. Hell the check valves could even be passing in both directions, but still wouldn't explain the above simple test case.

 

[TheWiggman]

Have you got a pic of the setup? I'm not sure specifically what you're referring to but it sounds like you've done everything right. Here's what I'd do (assuming you have JG fittings). Move onto the next step once each has been confirmed -

1. Turn the check valve BACKWARDS. This will lock air in the line between the reg and the check valve. Turn gas on then off. Put the valve underwater and check for bubbles. Wait an hour, check for a drop in presure. This will confirm a) whether the check valve works and b ) if the leak is in the regulator/bottle

2. Connect the lines to each keg, one by one, to the gas i.e. bottle > reg > gas line > disconnect (do not have connected to keg). Pressurise and come back later. If a drop in pressure is detected then there's a leak.

3. Charge all carbed kegs to the same pressure. Disconnect each. Wait an hour, then come back and re-connect gas. If an individual keg takes gas then there's a leak somewhere in that keg.

 

[GalBrew]

I've also had very slow leaks out of the gas post/gas disconnect interface on kegs. Very hard to diagnose with starsan/soapy water spray. I'd replace all of the post seals on the keg(s).

 

[stux]

I had slow leaks I couldn't diagnose with soapy water/starsan. I changed everything to JG. everything. Even the nipple on the regulator. (Which is where it was leaking!)

 

[DJ_L3ThAL]

Have you got a pic of the setup? I'm not sure specifically what you're referring to but it sounds like you've done everything right. Here's what I'd do (assuming you have JG fittings). Move onto the next step once each has been confirmed -

1. Turn the check valve BACKWARDS. This will lock air in the line between the reg and the check valve. Turn gas on then off. Put the valve underwater and check for bubbles. Wait an hour, check for a drop in presure. This will confirm a) whether the check valve works and b ) if the leak is in the regulator/bottle

2. Connect the lines to each keg, one by one, to the gas i.e. bottle > reg > gas line > disconnect (do not have connected to keg). Pressurise and come back later. If a drop in pressure is detected then there's a leak.

3. Charge all carbed kegs to the same pressure. Disconnect each. Wait an hour, then come back and re-connect gas. If an individual keg takes gas then there's a leak somewhere in that keg.

Yep will take and upload some pics tonight into the thread for reference.

1. Has more or less been checked but with the gas splitter tee and ball valve. I'll check with just the check valves to be sure but I am certain there is a leak on the reg, line or bottle.

2 & 3 I'll do once I am confident my bottle and regulator are not leaking, thanks!

I've also had very slow leaks out of the gas post/gas disconnect interface on kegs. Very hard to diagnose with starsan/soapy water spray. I'd replace all of the post seals on the keg(s).

Yep, replacing those will be done for sure!

I had slow leaks I couldn't diagnose with soapy water/starsan. I changed everything to JG. everything. Even the nipple on the regulator. (Which is where it was leaking!)

I have a setup owned by my mates with a 6kg bottle and all JG fittings (got this a year after getting mine and learning what is better)... I'll borrow it back and test my regulator with the JG fittings and vice versa and see how that goes.



So no one can confirm or deny whether the KK gas line can permeate pressure out, or if the CO2 bottle valve assemblies themselves could be faulty/leak? The loose metal inside the bottle is a concern is it not?

 

[woodwormm]

I've found with several push fittings from kk if the hose doesn't go straight in it can leak. I was getting a leak when closing the door put pressure on the pipe. .. but it was evident enough when you bend the pipe at the fitting it would leak too.

 

[TheWiggman]

I have a KK reg like yours and it got a leak out of one of the guage threads. This was my fault though because I did it up, though that was KK's fault because I replaced one of the guages myself (first one was faulty).

I find it hard to believe there could be a leak in the bottle assembly, those things are very robustly designed to hadle the extreme pressures they're under. The loose thing internally is not uncommon. On the weekend I swapped an empty LPG bottle and it had a rattle inside.

I use KK gas line on part of my system and no, doesn't leak like you're saying. Permeate yes but not enough to notice over the course of days or weeks.
Was going to say if it was that bad they wouldn't sell it but has you heard of their elements?

 

[marksy]

How much pressure are you loosing? Are you talking about bottle side gauge or keg side?



Did you check the quick connects were on correctly? Or the seal around the main opening of the keg?

 

[blekk]

I've found with several push fittings from kk if the hose doesn't go straight in it can leak. I was getting a leak when closing the door put pressure on the pipe. .. but it was evident enough when you bend the pipe at the fitting it would leak too.

I had the same issue with quick disconnects, if it wasn't clicked in straight it would leak very slowly when any slight pressure was put on the hoses.

 

[marksy]

My pressure relief valves on the cornies always cause me troubles. They seem to come loose.

 

[Camo6]

I doubt this is any help DJ but I cleaned and pressure tested all of my kegs the other day and found one had lost all pressure overnight. Eventually found a pinhole in the weld around the top of the keg. Two seconds with the TIG and I can now justify to SWMBO the cost of argon rental!

 

[DJ_L3ThAL]

I have a KK reg like yours and it got a leak out of one of the guage threads. This was my fault though because I did it up, though that was KK's fault because I replaced one of the guages myself (first one was faulty).

I find it hard to believe there could be a leak in the bottle assembly, those things are very robustly designed to hadle the extreme pressures they're under. The loose thing internally is not uncommon. On the weekend I swapped an empty LPG bottle and it had a rattle inside.

I use KK gas line on part of my system and no, doesn't leak like you're saying. Permeate yes but not enough to notice over the course of days or weeks.
Was going to say if it was that bad they wouldn't sell it but has you heard of their elements?

Yes I have heard of their elements, also now thinking their regulators are of a similar quality (refer below).

How much pressure are you loosing? Are you talking about bottle side gauge or keg side?



Did you check the quick connects were on correctly? Or the seal around the main opening of the keg?

Depends on how long I left it, the 3bar tests were dropping to 2.5bar within a couple of hours. This morning the bottle only had 2.6bar left so I left the line holding that and came home 10hours later to 2.3bar (photo attached of how I had this mornings test setup.

My pressure relief valves on the cornies always cause me troubles. They seem to come loose.

Yep they are only hand tightened, even the brand new KK ones are the same, they can easily leak if knocked I have a habit of ensuring they are tight!

I doubt this is any help DJ but I cleaned and pressure tested all of my kegs the other day and found one had lost all pressure overnight. Eventually found a pinhole in the weld around the top of the keg. Two seconds with the TIG and I can now justify to SWMBO the cost of argon rental!

You just wanted to tell us you had an Argon bottle right!! I hope it's BOC ;-)


**UPDATE**
So I continued to overhaul the regulator tonight, managed to thread tape the PRV, pulled the two gauges out and then struggled with the cylinder stem, it would hardly budge. BUT ALAS! what was previously to me what appeared to be a "scratch/cut" in the metal coming from the edge of the thread where the steam connects into the regulator body, has now opened to appear somewhat like a crack in the regulator body. Haven't confirmed this is the cause (through underwater or soap spray), but sure as hell am going to return it to KK to discuss as it doesn't look like it's meant to be that way (refer photo attached).

 

[DJ_L3ThAL]

Also this is the nylon washer from my CO2 bottle, is this too shabby to be re-used? How sensitive are these washers? Anyone got exact dimensions so I can get a box of 50 from a nuts and bolts shop?

I've heard 3/4" OD, 1/4" ID and 1/8" thick, but unconfirmed? Suppose I can get my vernier caliper out... but nice to know what it SHOULD be...

 

[Camo6]

Not sure what it should be but I can assure you that you have found your life partner, you have a caring soul and will live a long happy life. I also do tarot readings and recommend you moisturise.

And did I mention I have argon?

Fwiw if the reg is cracked I'd be taking it back to KK and asking for a gas refill too.