S30 cap leaking...

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Wookie Monster

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Got a new pressure barrel which is fitted with a S30 cap for the small CO2 bulbs. Alas, it seems to have a leak somewhere- very little gas seems to stay atop my cider. I've greased every joint and seal, but it seems to be coming from the safety valve on the side. I previously had an ancient boots barrel whose gas fitting finally gave up and this was its replacement. So I'm a bit disappointed that it's leaking already.

So what am I doing wrong? Is there anything else I should be doing/checking? In the long term I might go to a separate bottle system so I can resurrect the old barrel too.
 
The pressure is normally kept within limits by:
  • An external "elastic band" that releases any excess pressure. If this seal is perished or displaced then the CO2 will escape.
  • An internal "elastic band" that acts like a Non-Return Valve and stops CO2 from escaping backwards from the injection point. Again, if this seal is perished or displaced then the CO2 will escape.
Apart from these two possibilities (they are easy to check out when the cap is off) the only other common sources of CO2 leakage are:
  • The "O" Ring inside the cap fails to engage because it is buckled, nipped perished etc. Again, easy to remove and check.
  • Not so easy (and much more common) is that the topsurface to the PB isn't smooth enough to allow the "O" Ring to seal. I have had to take a fine file to King Kegs and Wilko Kegs to cure this problem
I always smear a fine film of Vaseline on to the "O" Ring and the sealing surface on the top of the PB. It lubricates the thread and helps to ensure a tight seal by filling in any tiny imperfections. Personally, I never taste the Vaseline in the brew!

Enjoy.
 
i have taken apart and cleaned and refitted the seals on the s30 valve on two barrels, i also changed the barrel cap seal/

i cut the brown and black seals off and dipped the lotin citric acid and water to disovle the gunk

getting the seals back on was a nightmare, what you need is " lamb tail ring pliers" to do it easy i ended up with three cocktail sticks and a huge amount of swearing to get the back in place. well worth doing though as the valves i had were at least twenty years old
 
Got a new pressure barrel which is fitted with a S30 cap for the small CO2 bulbs. Alas, it seems to have a leak somewhere- very little gas seems to stay atop my cider. I've greased every joint and seal, but it seems to be coming from the safety valve on the side. I previously had an ancient boots barrel whose gas fitting finally gave up and this was its replacement. So I'm a bit disappointed that it's leaking already.

So what am I doing wrong? Is there anything else I should be doing/checking? In the long term I might go to a separate bottle system so I can resurrect the old barrel too.
In theory your PB purchase should function properly straight away without any intervention, so if it's new and it's faulty you should be talking to your supplier before you start fiddling about with it, and looking to get an exchange or a refund. PBs are notorious for leaking from any number of different places and you either like them or you don't, because although they are really convenient vs. bottles they are let down by leaks and can become more trouble than they are worth in spite of much careful attention by their owners.
 
Pretty much given up on mine (King Kegs), they used to be largely fine, but since they started leaking no amount of fetteling seems to have fixed them.

I now have two corny kegs and plan to get more :rolleyes:
 
Looks like I've fixed it. The overpressure release seal wasn't quite seated properly- refitted it and re-gassed the barrel and all seems well so far. athumb..
 
I want a keg but these and many,many,many other stories about gas leaks put me off.
As I no longer have an engineering works ( to the job properly) at my disposal I do worry about spending precious cash for one.
I have been torn between bottles and kegs for too long now.
 
I picked up 3 king/ rotokegs at a car boot so although they were dirty was a good deal at £5 each. They cleaned up with PBW and hold pressure ok. I had to replace the seals and two of the s30 valves because of corrosion, and made a lid spanner of sorts from plywood and a jigsaw.
Just keep your eyes open for them as homebrewing/ winemaking seems to be one hobby people take up then sell all their stuff, only to do it all over again.

I had over 24 demijohns at one point but two house moves meant they all had to go. Now I'm back up to 4.
 
Also worth noting that these pressure barrels only hold about 10PSI I gather. And this is barely enough to lightly carbonate and just on dispensing pressure, ok serving pressure less an issue on pressure barrels as you dispense via a tap of cause.

Anyway, from my experience with them even after I confirmed a proper seal I still thought I had a leak when injecting the co2 bulb as it was hissing away from the valve. Turned out things were fine but after a few days, because I had primed the pb with sugar the internal pressure had already near reached the safety limit and so injecting further co2 simply caused the excess to go expelled via the relief valve.
 
Also worth noting that these pressure barrels only hold about 10PSI I gather. And this is barely enough to lightly carbonate and just on dispensing pressure, ok serving pressure less an issue on pressure barrels as you dispense via a tap of cause.
The basic Youngs PBs are stamped with 'Maximum Working Pressure 15psi', although I was given a very old PB which was stamped 10psi.
I believe that one problem with dispensing beer from taps on PBs is that whatever the pressure inside the PB when the beer is pressure forced through the tap it experiences a venturi effect (i.e. the pressure is temporarily lowered) and some dissolved CO2 comes out of solution, and after it has passed through the tap the CO2 is not reabsorbed. This is most noticeable when dispensing beer from a 'high pressure' PB when all you get is foam not a stream of relatively highly carbonated beer. And in my view that's another reason why they are fine for low carb beers but not high carb beers (assuming of course the PB holds pressure in the first place wink...).
 
Dave 666 I think you have hit the nail on the head for me with "Even after when i confirmed a proper seal I thought I had a leak"
Its about confidence in the product.
 
Even in my Growlers, I only maintain 5psi pressure for carbonation and serving ('cos I hate "gassy beer" with a passion) and I can still get a glassful of foam from some of the PB taps..

All I do in these circumstances is pour the brew into a 1.5 litre jug and then decant it into the glass when it's settled. Simples!

BTW
Having wrestled for many years to tighten and loosen PB caps I spent some money and invested in one of these ...

https://www.amazon.co.uk/Draper-Redline-68813-Filter-Wrench/dp/B011R8ON60?ref_=fsclp_pl_dp_9

It's made my life a lot easier and (so far) I haven't had a single PB leak after attaching the cap with this tool.

Enjoy!
 
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