Cornies - Pressure Testing

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niall

Cornies - Pressure Testing

Post by niall » Fri Oct 27, 2006 2:47 pm

Any tips on pressure testing my cornie?

I connected the gas hose last night and filled the cornie full of water to test it. I turned the gas on and cranked the regulator up to about 30 psi, then turned off the gas and rocked the cornie back and forth, pressure dropped to around 20. I did this a couple of times to see if the CO2 was being absorbed. Each time I turned the gas back on the hissing died down quite quickly until I could hardly hear it so I figured I had no obvious leaks. Testing with a spray bottle filled with water and a little Fairy (insert "Carry On" joke here) revealed no obvious bubbling on any connections.

'So far so good' I thought, so I cranked up to 30 again for a few minutes and popped inside. It was when I came back out to the garage that I noticed a couple of things:

#1: When I came back out about 10 minutes later the regulator was now sitting at 40 psi - strange, I didn't see anyone mention this in the threads I've seen...

#2: I turned off the gas and removed the gas hose, including disconnect from the keg. Now I could hear hissing from the gas post.... Hmmmmm.

I popped the keg in the fridge and this morning I checked the pressure release valve quickly before leaving for work. It's holding pressure but I didn't have time to reconnect it to check the exact level it's at.

tribs

Post by tribs » Fri Oct 27, 2006 3:03 pm

Niall,

I sometimes get a leak on the gas post. Adding a tiny bit of vaseline usually does the trick.

I would empty the keg of liquids and turn pressure up to about 20psi and turn the gas off. See if the pressure drops over a day or so. Another option is to completely submerge in water to see if CO2 is escaping. If it is used, make sure you clean it first. Sometimes bits of crud can clog unseen little holes.

Spray or brush some soapy water on the connection between your regulator and gas bottle and turn the gas on to check for leaks here.

eskimobob

Post by eskimobob » Fri Oct 27, 2006 9:26 pm

Just trying to recondition three at the moment to get them all sealing properly. I've been pressurising them and then standing then upside down in a sink of water - any bubbles are obvious.

niall

Post by niall » Tue Oct 31, 2006 12:02 pm

Thanks for the tips guys, I'll have another look at it this evening and hopefully get up and running.

niall

Post by niall » Wed Nov 01, 2006 11:42 pm

Tonight I took the cornie apart, cleaned and sanitised, purged and racked my SNPA clone. I hooked the gas up and turned it on at 20 and vented the pressure. Then I decided to turn it to around 15 psi. It's not going below around 20 though as the pressure is not dropping beyond this even after pulling the pressure release valve - am I doing something stupid here?

On a positive note I tasted the beer while racking and I am amazed at how good at is. I've been reasonably satisfied with most of my brews but this is the first time I've been pleased to the point that I'd be happy to drink it in its own right as against drinking it because it's my own brew. It's been sitting in secondary for weeks on end with Cascade in a hop bag and the hop aroma and flavour is really working.

Vossy1

Post by Vossy1 » Thu Nov 02, 2006 12:33 am

Hi Niall, I'll assume you disconnected the cornie, or turned the gas off when venting the 20psi.

If you did neither then the gas bottle will keep re-filling the cornie to 20 psi as you vent it, so you'll always have 20 psi, until the gas runs out.

If you did disconnect the cornie from the gas did you zero the reg screw before re-attaching/re-opening the gas bottle.

If not the gas bottle will refill the cornie to 20 psi.

If you drop to 15psi when the cornie attached is at 20 psi you risk beer returning to the reg and that's why quite a few members use check valves in the beer line between cornie and reg.

What you need to do is disconnect the cornie and vent its pressure.
Zero the reg screw.
Re-attach the cornie and open the reg to 15 psi 8)

Even easier, I'll find the link for this.

http://jimsbeerkit.co.uk/forum/viewtopi ... cornie+tip

Here's the gauge

http://www.seastarsuperbikes.co.uk/main ... etail=1812

This tyre pressure gauge tubing easily pushes into a 3/8th JG fitting.
Attach the JG fitting to a disconnect and onto the cornie and then you can drop the pressure from 20-15psi without having to lose all the co2 :wink:

Hope some of this helps :wink:

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Post by Andy » Thu Nov 02, 2006 9:34 am

Niall - sometimes the gauge needles stick, give it a few taps with your finger and see if the needle drops down.
Dan!

niall

Post by niall » Thu Nov 02, 2006 11:30 am

I think I did vent with the gas switched on so that may be my problem. I'll try again tonight and report back.
If you drop to 15psi when the cornie attached is at 20 psi you risk beer returning to the reg and that's why quite a few members use check valves in the beer line between cornie and reg.
:o oh, must watch out for that!

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Post by Andy » Thu Nov 02, 2006 11:44 am

It's only a prob if your cornie CO2 in tube is submerged in the beer or if you manage to connect the CO2 disconnect to the beer out post - this *is* possible! :oops:

Venting with the CO2 on isn't going to get you very far as you've found out :lol:

I'd recommend leaving the CO2 cylinder turned OFF and only give it an ON/OFF blip when you need some gas. That way if you've got any leaks in your system then you're not going to end up with an empty cylinder and a room full of CO2 :shock:
Dan!

niall

Post by niall » Thu Nov 02, 2006 12:50 pm

'd recommend leaving the CO2 cylinder turned OFF and only give it an ON/OFF blip when you need some gas. That way if you've got any leaks in your system then you're not going to end up with an empty cylinder and a room full of CO2
Cheers Andy - I presume I need to leave the gas turned on though until the beer is force carbonated?

tribs

Post by tribs » Thu Nov 02, 2006 12:54 pm

Andy wrote:I'd recommend leaving the CO2 cylinder turned OFF and only give it an ON/OFF blip when you need some gas. That way if you've got any leaks in your system then you're not going to end up with an empty cylinder and a room full of CO2 :shock:
Thats exactly what I do. Once bitten, twice shy :wink:

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Post by Andy » Thu Nov 02, 2006 2:38 pm

niall wrote:
'd recommend leaving the CO2 cylinder turned OFF and only give it an ON/OFF blip when you need some gas. That way if you've got any leaks in your system then you're not going to end up with an empty cylinder and a room full of CO2
Cheers Andy - I presume I need to leave the gas turned on though until the beer is force carbonated?
No, just give it a blip every now and again.. Also roll the cornie around on its base to encourage CO2 to go into solution.
Dan!

niall

Post by niall » Fri Nov 03, 2006 11:48 am

Last night I noticed that the needle on the pressure gauge wasn't dropping below around 18 PSI even after I turned off the cylinder and regulator and shook, vented etc. I figured it may not go below this as this was what was in the keg, but it did seem strange that it wasn't going any lower with everything switched off and the grey disconnect removed. So I unscrewed the regulator from the cylinder, still no change.

I have a Widget bottle setup (with Soda sh so it's got a control handle/gauge) for Nitrogen/CO2 do I decided to swap the gauge on this with the gauge on my regulator. It showed zero. I cranked it up to 30 and turned it down, again it won't go down below 15 but this may be the pressure in the keg. Meanwhile the original gauge, now sitting on its lonesome is still showing about 18 PSI. Is the regulator dodgy or is there yet another factor that I haven't twigged?

Again my gas poppet is leaky as when I shake the keg and remove the grey disconnect some beer froths up through it. I thought I had sorted this out when I cleaned and reassembled but obviously not.

niall

Post by niall » Fri Nov 03, 2006 12:02 pm

Thanks DaaB. I think I tried that but I can't be sure so I'll give it another go. Would this explain why the needle on the gauge I removed didn't drop afterwards?

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Post by Andy » Fri Nov 03, 2006 12:11 pm

As DaaB mentions - when you take the grey disconnect off the cornie post the reg. gauge won't change as it's showing the pressure in the pipe from the regulator to the grey disconnect. It seems to me that your system is operating correctly. Sometimes it pays to stand back and think how the system is working before taking stuff apart! :wink:
Dan!

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