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General Category => Kegging and Bottling => Topic started by: enso on August 24, 2010, 06:41:03 PM

Title: How do I determine if a regulator is leaking?
Post by: enso on August 24, 2010, 06:41:03 PM
I continue to be driven crazy trying to find the CO2 leak in my system.  I have replaced hoses, redid connections and gaskets, everything I can think of.  Still leaking.  I believe I know the general source of the leak from shutting off different parts of the system.  It seems to be somewhere between the manifolds in the fridge and a T of shutoffs after the primary regulator.  I am hoping I am wrong but starting to wonder if it is the bank of 3 secondary regulators.  I have checked the connections and they appear to be sound.  So I am wondering if there is a leak in the regulators themselves.  Man I hope I am wrong.

How can I rule this out?  If there is a leak can it be fixed?  They are perlick regulators.  Used I think.  I bought them from American Science and Surplus.  They were working well for several years.
Title: Re: How do I determine if a regulator is leaking?
Post by: tschmidlin on August 24, 2010, 07:06:40 PM
Have you tried spraying with soapy water to find the source of the leak?
Title: Re: How do I determine if a regulator is leaking?
Post by: saintpierre on August 24, 2010, 07:11:13 PM
Assuming a pressurized keg and your keg/connections don't have a leak wouldn't a pressure drop in the regulator (when you turn the gas on) indicate a leak?
Title: Re: How do I determine if a regulator is leaking?
Post by: gordonstrong on August 24, 2010, 08:05:07 PM
Yup, spray with soapy water and watch for bubbles. Keep some handy in a spray bottle for troubleshooting leaks.

Are you able to swap regulators and see if you still have the problem?
Title: Re: How do I determine if a regulator is leaking?
Post by: bluesman on August 24, 2010, 08:07:25 PM
A spray bottle of Starsan will also do the trick,  plus it will help keep your beer fridge sanitized.  ;)
Title: Re: How do I determine if a regulator is leaking?
Post by: enso on August 25, 2010, 12:41:14 PM
Yes, I have been spraying all connections insescently with star san, even dunking ones that I can into a container of star san.  I just can't find any leaks.

Here is what I have done briefly.   ::) 

I first checked the primary regulator.  Sprayed the connection between the tank and regulator.  No bubbles.  Charged up the regulator noted where the needles where on the gauges and shut off the CO2 bottle.  Left it for about a day.  No drop in pressure.

The line going out of the primary regulator is a short hose connected with a swivel hose barb and it travels to a T junction with 2 shutoff valves.  I sprayed the connection coming out of the primary with star san with the CO2 open.  No bubbles.  I then dunked the T connection with the shut-off valves turned off.  No bubbles.

One shut-off goes directly to a barbed swivel attached to a flare fitting QD.  I opened that valve and dunked the QD in star san.  No bubbles.  Shut the valve.

The other side of the T goes to a bank of 3 secondary regulators.  I turned the pressure control screws all the way open so no pressure was going out of the regulators and opened the valve at the T.  I sprayed the barb fitting going in to the regulators, the fittings between the regs, and the end plug.  No bubbles.

The first 2 regulators in the series are each connected to a two way manifold inside the kegerator.  The third reg. goes directly to a barb swivel and flared QD.  I shut all the manifold valves off and had the QD not connected to a keg.  I then pressurized one reg. at a time, noted the pressure, and turned off the gas back at the T.  I come back in about 8 hours and...  The pressure has dropped.  I repeat the process with each regulator individually.  Same deal.

I replaced all the hoses going in to the regulator bank and traveling to the manifolds and QD with new 3/16" beverage tubing and checked them again.  Still had a pressure drop.  If left long enough it would drop all the way to 0 by the way.

So?  Is it the regulators?  Can anything be done?  Am I missing something to check?

 >:(

Title: Re: How do I determine if a regulator is leaking?
Post by: gordonstrong on August 25, 2010, 02:49:33 PM
Could you post a picture? I'm having trouble visualizing your setup.

Are the bank of three regulators one unit, or three individual regulators hooked together somehow? Can you isolate/replace the first regulator in the series? That seems to be a common part of your problem.

Did you test the manifolds inside the kegerator? Are you able to cap off the out side of the regulators?

I tend to think you're right that it's a problem with those regulators but I would try to eliminate all down-stream components to verify that theory. I don't know how much you can attack pieces of the regulator, though. If it's one unit, what model?
Title: Re: How do I determine if a regulator is leaking?
Post by: bluesman on August 25, 2010, 04:40:27 PM
A picture would certainly help. 

I think you need to isolate (leak test) each component independently through process of elimination which is done one step at a time.  If the keg holds pressure then check the regulator by swapping it out with a known good regulator,  etc...  If you don't have a second regulator you have to rely on soapy water to test each component from the cylinder to the keg.
Title: Re: How do I determine if a regulator is leaking?
Post by: enso on August 25, 2010, 04:48:17 PM
Okay, here we go.

Starting at the CO2 bottle the line out goes to a T with two shut-offs.  One goes to a QD as shown, the other travels up to the bank of secondary regs.  

http://www.flickr.com/photos/68291744@N00/4926411257/in/photostream/]http://www.flickr.com/photos/68291744@N00/4926411257/in/photostream/

Next we have the three secondary regulators.  They are attached via pipe nipples and the end of the line is plugged.

http://www.flickr.com/photos/68291744@N00/4927004748/in/photostream/
the front

http://www.flickr.com/photos/68291744@N00/4926408647/in/photostream
the back

http://www.flickr.com/photos/68291744@N00/4926412545/in/photostream
the end.

Next, the first 2 travel on to manifolds inside the kegerator.  Normally these are inside.  I pulled them out and reattached to test them easier.

http://www.flickr.com/photos/68291744@N00/4926406739/in/photostream/

The third regulator just goes directly to a QD.  I did not take a picture of that.

That give a clearer picture or perhaps suggest a problem area?

The regulators have a sticker with the following information
"Perlick corp. Model 40115, Secondary CO2 compressed gas regulator 366M, 1800 Maximum Inlet Pressure."
Title: Re: How do I determine if a regulator is leaking?
Post by: enso on August 25, 2010, 04:56:16 PM
Please stand by, techincal difficulties...  Where are my PICS!?

Sorry folks.  Best I can do is post the links to the flickr page.  I cannot seem to embed the pics properly.
Title: Re: How do I determine if a regulator is leaking?
Post by: bluesman on August 25, 2010, 04:59:26 PM
I think you need to isolate each component one at a time and through process of elimination you'll detect the source of the leak.  Start with the CO2 cylinder and work through it one component at a time using one regulator in-line to the keg.  Attach a pressure gage to the keg and pressurize the keg to 30psi.  Use soapy water and start the process of elimination by introducing one component at a time.
Title: Re: How do I determine if a regulator is leaking?
Post by: tschmidlin on August 25, 2010, 05:27:16 PM
You can take the regulator bank apart and isolate them individually for testing.  It'll be a total pain, but it's the best way to do it I think.  I'm going to be doing the same thing pretty soon, I've got a leak somewhere in the new system I just put together.  I'm hoping it's just one of the kegs.
Title: Re: How do I determine if a regulator is leaking?
Post by: enso on August 25, 2010, 09:09:28 PM
I think you need to isolate each component one at a time and through process of elimination you'll detect the source of the leak.  Start with the CO2 cylinder and work through it one component at a time using one regulator in-line to the keg.  Attach a pressure gage to the keg and pressurize the keg to 30psi.  Use soapy water and start the process of elimination by introducing one component at a time.

Pressure gauge?  Something else I need to buy?  ...and then still have a leak!
Title: Re: How do I determine if a regulator is leaking?
Post by: enso on August 31, 2010, 03:41:28 PM
So, still no luck.  I made up a different soap solution for leak checking rather than star san.  I used dish soap and some glycerin.  I sprayed everything!  I mean everything, connections and all sides of the regulators.  Not a sign of bubbles, other than from the spraying action itself.  I have built a keg pressure tester/bleed valve.  Not sure if that will tell me anything as I have not even gotten to the stage of connecting the kegs...

This sucks.
Title: Re: How do I determine if a regulator is leaking?
Post by: jalynn2 on September 01, 2010, 01:02:12 AM
Watch the gas connectors on the kegs -- I have had leaks there myself even though the o-rings look good. I solved my problem with a light coating of keg lube on the o-rings on the valve.
Title: Re: How do I determine if a regulator is leaking?
Post by: beveragebob on September 06, 2010, 01:18:15 AM
Maybe it could be a bad oring on the gas side of a keg? I've had that happen before. Check your Orings, keg lube them all if they look decent and check for pressure drops on the regulator system.
Title: Re: How do I determine if a regulator is leaking?
Post by: enso on September 08, 2010, 06:11:04 PM
The gas connectors on the keg would be a possibility if I had them hooked up...   ;)

Okay, so I have not had time to rip the whole thing apart and rebuild.  I did make a pressure tester/bleed valve though.

It has me stumped.  What does this tell me?

http://flic.kr/p/8zhv8D (http://flic.kr/p/8zhv8D)
I opened the middle regulator with the pressure tester attached.  There was a slight discrepency in the pressures listed but I figure that was just different gauges.  I left it this way overnight.  Today I find that the test gauge gizmo is still reading about the same pressure, maybe a .5 unit drop.  The regulator itself, several unit drop.  The blue tap marks where the needle was t start with on the gauges.

What does this mean?
Title: Re: How do I determine if a regulator is leaking?
Post by: tschmidlin on September 08, 2010, 06:20:44 PM
I'm assuming gas could not flow backwards to the other gauge, either because of a one-way valve or because you shut off the valve?

I'm also assuming you shut off the gas at the tank?

Maybe I'm missing something, but it looks to me like you've narrowed it down to gas bleeding out of that center gauge.  I know rebuild kits are available, for example this one (http://morebeer.com/view_product/16191//NADS_Regulator_Rebuild_Kit), but I have no idea how hard it is to rebuild a gauge.

Title: Re: How do I determine if a regulator is leaking?
Post by: enso on September 08, 2010, 08:26:51 PM
I did not shut it off at the tank but I did shut it off upstream from the bank of regulators.  I should say, I also did this same test to the first regulator in the series.  It too did the same thing.  Only it did not "bleed" quite as severely.

It seems strange to me that if the regulator is leaking that it would not also drain the pressure from the tester gauge.
Title: A HA!
Post by: enso on September 09, 2010, 03:46:49 PM
Well, I figured that part out anyway...

So the reason my tester was not losing pressure was that I forgot I had check valves installed on the outputs of the regulators.  I was reminded of that when I finally ripped the whole thing apart today.

Which leads me to believe the leak is almost certainly coming from the regulator bank.  Whether it is a regulator, or all of them, or just a connection is yet to be determined.

I will now test each regulator seperately.

Thanks for all the advice thus far.  Hopefully this will get resolved.
Title: Re: How do I determine if a regulator is leaking?
Post by: tschmidlin on September 09, 2010, 04:36:59 PM
Yeah, check valves, that's what I meant by "a one-way valve".  I have trouble coming up with the right words sometimes :)

Well, at least you've narrowed it down a bit.  Let us know how it goes.
Title: Re: How do I determine if a regulator is leaking?
Post by: enso on September 09, 2010, 11:30:04 PM
Yeah, check valves, that's what I meant by "a one-way valve".  I have trouble coming up with the right words sometimes :)

Well, at least you've narrowed it down a bit.  Let us know how it goes.

Oops.  Guess i missed that or it only registered subconsciously.  I would have come to my conclusion faster had I.  Yeah one way valve, check valve, same difference.
Title: Re: How do I determine if a regulator is leaking?
Post by: enso on September 10, 2010, 12:54:53 PM
Well first test is a fail.  I hooked up one of the secondary regulators alone with the pass through plugged and my pressure tester hooked up to the check valve outlet last night.  This morning both gauges were registering a drop in pressure!  I had sprayed all connections with soapy water and witnessed no bubbling.

I even used special gas teflon tape I found at the hardware store.  I had not seen that before.  It is thicker and less stretchy/flimsy with a slightly yellow tinge to it.  It is intended for use with propane, natural gas etc. so I figure it was good for this purpose.

AHHHH!!!!   >:(

I am thinking I may and try opening up one of the secondary regulators today to see what I can see.  Never done that before so I may be sacrificing the regulator as it may get damaged...   ::)

One other possibilty I am considering is that the gauges themselves are leaking?  As I was reassembling the secondaries (rewrapped the threads and put gauges, and fittings back on) one of the gauges got damaged somehow and is no reading 8 psi all the time.  I started another thread inquiring about gauges.
Title: Re: How do I determine if a regulator is leaking?
Post by: enso on September 18, 2010, 02:58:34 PM
At long last!  The leak source has been found!  It was not the regulators after all.  It was the cheap @ss ball valves I got from  morebeer have had problems with in the past.  Trouble is, I never saw any leaking from them despite dunking the entire junction under soapy water!  I just finally got frustrated and removed the T section they were a part of as a last ditch effort.  No more leaks.

Thanks everyone for your help along the way.  Man that was frustrating.
Title: Re: How do I determine if a regulator is leaking?
Post by: tschmidlin on September 18, 2010, 04:31:41 PM
Wow, what a pain!  Well, at least it's done. :)

Sorry about the hose problem too, man, it's almost enough to make someone want to stop having homebrew on tap . . . nah.