Corny keg question

[fury_tea]

Do you turn the co2 off between uses?

A couple of months back I lost all my gas to a leak in my system. I sprayed everything with washing up liquid and found a couple of very slow leaks on the plastic John Guest "screw in" line adapters. Bit of PTFE sorted them out and I thought everything was dandy. No more leaks to be seen.

Well I'm still paranoid about losing gas so now I always turn the gas off when not in use.

One thing I've noticed is the 2nd pressure gauge (that shows you there's pressure in the tank) is usually in the red a couple of days later (my heart drops each time it happens thinking I've lost my gas again), is this normal or is it indication that I've still got a leak somewhere?

Ta

 

[Graz]

My CO2 stays on if I'm carbonating something, wouldn't work very well otherwise, but if all kegs are carbed up then I turn it off. Also paranoid about losing the gas.

I do have secondary regulators and each one of those has a lever to turn on or off the gas supply to each keg so I will turn also off individual ones if they don't need more gas.

My main regulator also does that on the tank gauge. Can't find any leaks so do find it odd.

 

[foxbat]

One thing I've noticed is the 2nd pressure gauge (that shows you there's pressure in the tank) is usually in the red a couple of days later (my heart drops each time it happens thinking I've lost my gas again), is this normal or is it indication that I've still got a leak somewhere?

This might be gas in the high pressure part of the regulator leaking out through the thread on the cylinder valve that's only possible when the cylinder valve is closed. I saw a diagram of how the cylinder valve works on another forum once. It's like a plunger that's either fully down and closed, at which point there may be a leak path back out of the high pressure part of the regulator up through the top thread of the cylinder valve.

Worse is that if you don't open it fully then you've also got a leak path out of the cylinder thread because the plunger system needs to come all the way up and seal at the top.

Hard to explain without a diagram. I'll see if I can find it.

 

[PhilBrew]

Do you turn the co2 off between uses?

... yes, I turn the CO2 off ... unless carbonating, like Graz says

pressure gauge (that shows you there's pressure in the tank) is usually in the red a couple of days later ... is this normal or is it indication that I've still got a leak somewhere?

... that happens on mine too ... I can't say there definitely isn't a leak .. but I don't figure there necessarily HAS to be a leak for this to happen ... here's what I think is probably happening (I don't have my cornies temp controlled but even if you do the temperature will fluctuate slightly over time) ... at some point (in the middle of the night, say) the temperature of the beer in the corny drops, and it can absorb more CO2 into it ... this happens and reduces the pressure in the headspace above the beer below the pressure that you've set the secondary regulator to, so the valve opens (to let more CO2 in to "correct" that) ... at this point there's a relatively small volume of gas in the pipes between the closed cylinder valve and the corny so the pressures even out in that space ... this slight variation on CO2 take up makes no difference to the pressure shown on the secondary meter (12 psi, say, or whatever you've set it to) ... but such a low pressure shows up as virtually zero on the primary regulator meter

I may be delusional and all my CO2 may be leaking all over the place ... and I turn the supply off at the cylinder whenever I can, just in case ... but thinking this is probably what's happening, is what helps me sleep at night

Cheers, PhilB

 

[foxbat]

Hard to explain without a diagram. I'll see if I can find it.

Aha, found the diagram. Here it is:

https://www.homebrewtalk.com/threads/co2-leak-or-normal.194447/#post-2261999

 

[HarryFlatters]

One thing I've noticed is the 2nd pressure gauge (that shows you there's pressure in the tank) is usually in the red a couple of days later (my heart drops each time it happens thinking I've lost my gas again), is this normal or is it indication that I've still got a leak somewhere?

That's normal, mines does it too. I'm also paranoid about losing all my gas at the moment as I will be unable to get a refil for the forseeable, so I'm switching off my gas when I'm not using the system. I turn it on periodically to ensure that everything is suitably carbonated when I want a beer.

 

[peebee]

… Well I'm still paranoid about losing gas so now I always turn the gas off when not in use.

One thing I've noticed is the 2nd pressure gauge (that shows you there's pressure in the tank) is usually in the red a couple of days later (my heart drops each time it happens thinking I've lost my gas again), is this normal or is it indication that I've still got a leak somewhere?

Ta

Paranoid?

Nah. You haven't even scratched the surface! This from part of my dispensing system that turns the cylinder off automatically after a few minutes …

And surely you know by now the "tank pressure" indicates naff all? CO2 Management Primer (penultimate paragraph).

 

[phildo79]

I used to turn mine off but leave the disconnect on. I then read that wasn't a great idea because beer might shoot back up the line. I have my tank in the fridge, behind two kegs, so getting at it to turn it off is awkward. So, through laziness, I just unhook the disconnect when I am not using the kegs and leave the gas on.

Touch wood, no leaks so far. Although I do not have the standard line between the reg and the disconnect. I bought myself some coiled tubing for more flexibility. The only ones I could find at a reasonable price were metric measured so it isn't a perfect fit. They are hard to push in and a nightmare to remove so good luck to any gas that finds a way out.

 

[peebee]

Do you know what is worse than that drawing I posted?

A. The fact that I turned it into reality!

This is the cylinder complete with solenoid on/off valve (on a very diminutive primary regulator):

And this is the timer switch that cuts the CO2 after a few minutes. Note one of the dispensing control boxes also powered on the same auto-off circuit with individual switches to enable the gas on individual kegs (and with liquid solenoid valves to isolate beer to the tap).

But the best advice I can give (which might seem crazy on top of all the precautions I've taken): Have a full second cylinder kicking about, just in case. (And a full Sodastream cylinder just in case "just in case" isn't good enough).

After this virus thing is over, perhaps you'll be interested if I start courses "Risk Assessment for Lunatics (by someone who ought to know)".

 

[fury_tea]

Do you know what is worse than that drawing I posted?

A. The fact that I turned it into reality!

This is the cylinder complete with solenoid on/off valve (on a very diminutive primary regulator):
View attachment 26189
And this is the timer switch that cuts the CO2 after a few minutes. Note one of the dispensing control boxes also powered on the same auto-off circuit with individual switches to enable the gas on individual kegs (and with liquid solenoid valves to isolate beer to the tap).
View attachment 26190
But the best advice I can give (which might seem crazy on top of all the precautions I've taken): Have a full second cylinder kicking about, just in case. (And a full Sodastream cylinder just in case "just in case" isn't good enough).

After this virus thing is over, perhaps you'll be interested if I start courses "Risk Assessment for Lunatics (by someone who ought to know)".

Amazing. You should sell these to paranoid homebrewers. You'd make 10s of pounds!

Seriously though that is an impressive set up. I had an idea to do similar using solenoids after I lost my first co2 tank. Never got past the "hmm I wonder if..." stage though.

 

[peebee]

… I just unhook the disconnect when I am not using the kegs and leave the gas on. …

Careful with that. I've had to clean and re-lube a number of my disconnects because they leaked about the pin (and even the "cap" on some). Not difficult to renovate (just be cautious of the soft plastic threads - don't apply a lot of effort). Inside the disconnect you only find a plunger (with O-ring seal) that is normally visible as the "pin", and a spring. There is a seal on the cap (which opens by unscrewing with a large flat screwdriver in the obvious slot - plastic, so be careful).

 

[Honk]

I only connect up the gas when I need it. That is when the pressure gets too low to pour at a decent pace. Even when carbonating I just give it a blast of gas, then top it up later on.

Works for me but I like a low level of carbonation.