Pressure reading during carbonation of a keg

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Westo

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As i have been having mixed results when force carbing a keg with the rocking or "ross" method i thought id try the old set n forget method, I have already come across something that has me worried if something is wrong or not.

so heres my problem or question....

after transferring cold beer that had been CC from the fermenter to the keg i then went about gasing up the keg and burping it as i normally would, I then set the pressure on the regulator to 30psi(im still experimenting with what pressure works best for my set up) i then connected the gas QD to the keg and put it back in the fridge where i plan to check on it in a couple of days... a couple of hours later i notice that the pressure guage now reads 24psi (the main pressure or whats left in the cylinder guage is still at full where it was when i started). this also happend to me the other day with another keg.

the gas cylinder sits outside the fridge. So Is this normal?? or is something not right here?

Is it a result of the cold liquid absorbing the C02 causing the pressure to drop?
should i turn the pressure back up to 30psi or leave it?
the fact that the cylinder pressure isnt dropping suggest that there is no leak?

i have been trying to googlewack and search for an answer with no luck.

If anyone can help me out be much appreciated .... cheers guys

Westo
 
Sounds like the regulator might have a fault. I've had the opposite problem where the pressure gradually crept up. In my case it must have bee a bad seal in the reg itself. Retailer (Craftbrewer) replaced it under warranty. Not sure exactly what kind of fault would explain your situation though. If the system was leaking the pressure gauge would still give a fairly constant reading (unless you had a serious leak which you'd probably notice, not least because you'd soon run out of gas, or all the breathable air in your house would be displaced by CO2).

It's worth noting that until you're almost out of gas, the cylinder pressure reading will not change (might fluctuate a bit due to temperature), as the stored CO2 is liquefied, so looking at the high pressure gauge might not inform you of a leak until it's way too late.

What regulator have you got?
 
I think you will find the regulator setting is actually 24, but with minimal headspace slightly more gas is getting through before the reg functions completely. Gas is then absorbed and the system equilibrates.

Slightly OT but I think your experiments will lead to the conclusion that 30psi is way too high.
 
going to go slightly OT but whats with all the chuck 30-40psi at it and wait a couple of days methods, we aren't in the mega swill game and good beer takes patience,

I have 4 taps on my fridge and spare kegs so theres always 1 chilled keg full ready under slight CO2 pressure ready to go on tap when one blows but not fully carbed, I do have one secondary reg per keg which does make it easier, but you get the idea

I have never set my pressure at anything more than the desired carbonation pressure for the style of beer I am pouring, admittidly it takes a week but you get the perfect pour from the first glass to the last, doesn't that seem like a better option than whacking a load of PSI at it and shake or guess when it;s correctly carbed?
 
rehabs_for_quitters said:
going to go slightly OT but whats with all the chuck 30-40psi at it and wait a couple of days methods, we aren't in the mega swill game and good beer takes patience,

I have 4 taps on my fridge and spare kegs so theres always 1 chilled keg full ready under slight CO2 pressure ready to go on tap when one blows but not fully carbed, I do have one secondary reg per keg which does make it easier, but you get the idea

I have never set my pressure at anything more than the desired carbonation pressure for the style of beer I am pouring, admittidly it takes a week but you get the perfect pour from the first glass to the last, doesn't that seem like a better option than whacking a load of PSI at it and shake or guess when it;s correctly carbed?
Yes good beers take patience, but it is good to know where can speed up without compromising on beer quality, and this is one of them!! Force carbonating at 30-40psi for 1-2 days is not going to compromise your beer or turn it into megaswill. Cutting short your fermentation will. When I had less kegs tI used to force carb at 36psi for 36 hours to ensure I had an uninterrupted supply of beer. Now I have more kegs I can set and forget. Not everyone has your system, so it is different strokes for different blokes.
 
Yeah I actually totally agree with your views, it really just seems a bit hit and miss carbing at high pressure for so many hours give or take a few , then the question gets asked why does my keg pour 50% head,

Maybe I am just old fashioned and like my carb levels to be to style to bring out the best in the beer, it's bit like a 5 day test everything falls into place over time :)
 
So as for the regulator? that is my main concern here does that fact that it has dropped whilst carbonating mean the regulator is stuffed? it doesnt do that when im serving an already carbonated beer infact it holds at 6 ,10 or 12psi or whatever i set it to , just only noticed it whilst force carbing the beer.
 
Has it remained stable at 24psi since? If so the reg is probably OK. Sometimes when you turn down the pressure, it may take a while to register on the reg because the beer has to absorb the CO2 in the headspace before the pressure will change on the dial.
 
yeah it actualy ended up dropping to 20psi late last night and when i checked just then (almost 24hrs later) its still at 20psi. once the inside of the keg hits equilibrium(i think thats the right term) should i expect the reg pressure to start climbing back to 30psi?
 
I wouldn't expect it to climb back to 30psi. When setting your pressure it is best to start low and dial up. When you set the pressure high and then dial down, your gauge will continue to read high until the CO2 is absorbed form the headspace, meaning you will have little idea what pressure you have it actually set to. I suspect you started high (30psi) and turned your dial down. What you didn't realise is that you had adjusted the pressure to 20psi and it just took sometime for the CO2 to be absorbed into the beer and for the real pressure you show on the gauge. I would consider backing of your pressure now to your serving pressure: for me that is 12psi that gives me 2.5 volumes at 4 degrees which is good for a lot of beers. It may take a few days to get the carbonation where you like it, but it better than over-carbonating and spending a week burping your keg to get rid of the carbonation.
 
Black n Tan said:
I wouldn't expect it to climb back to 30psi. When setting your pressure it is best to start low and dial up. When you set the pressure high and then dial down, your gauge will continue to read high until the CO2 is absorbed form the headspace, meaning you will have little idea what pressure you have it actually set to. I suspect you started high (30psi) and turned your dial down. What you didn't realise is that you had adjusted the pressure to 20psi and it just took sometime for the CO2 to be absorbed into the beer and for the real pressure you show on the gauge. I would consider backing of your pressure now to your serving pressure: for me that is 12psi that gives me 2.5 volumes at 4 degrees which is good for a lot of beers. It may take a few days to get the carbonation where you like it, but it better than over-carbonating and spending a week burping your keg to get rid of the carbonation.
yeah i set the guage to 30psi but i did not dial it down infact i havent touched it,, it has just gone down to 20psi on its own
 
What I mean is at the time when you originally set the pressure, you may have may have set it a bit high and then turned down the dial to compensate. Doesn't really matter, but the gauge now appears stable so I suspect there is nothing wrong with your reg. If it starts behaving erratically then you might need a new reg. Another tip when you can turn down the dial is to burp the keg to get an accurate read on pressure.
 
I've tried to shake, rattle and roll method with varying results, I've tried the carb under high pressure method with OK results, but I do find the best method is leave it for close to a week at serving pressure. Unfortunately, demand often outstrips supply at my place so I often have a dry tap, but even then, I prefer to grab a case of something and wait a few extra days then rush the process. There's also something to be said for the theory of when you have your gas setup pouring right, don't touch it! It's really not that much longer, I'm going to keg an English Bitter on Sunday and it will be right to pour by Friday. In my experience 4-5 days at serving pressure sees it carbonated. The only time I do vary from this is if I know I've got friends coming over, and it's not in the keg yet, I'll do the high pressure carb over 24 hrs.
 
This happened to me the very first time i started kegging and is due to the absorption of CO2 in the beer. Just crank up the regulator a little more and it will eventually level out and stabilize.
 
ricardo said:
This happened to me the very first time i started kegging and is due to the absorption of CO2 in the beer. Just crank up the regulator a little more and it will eventually level out and stabilize.
ok should i wait next time for it level out before turning it back up to where i want it or as soon as i see the pressure has gone down? I just checked the keg about 1 - 2hrs ago and the beer has slight carb but needs more time so i bled the keg reconnected the gas to 30psi and now see the dial is at 28psi should i turn it back to 30 now or wait longer?
 
If you have your gas turned on your reg pressure should not drop below 30psi or what ever you have it set at.
 
I prime my kegs with dextrose...50 grams/ 20 litres before putting them in the kegerator.
Can anyone offer me advice as to whether I can buy a pressure gauge that is also a pressure release valve,or, better still
Is there a genius on AHB that has made one?
 
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