A question for beer engine/corny users

[paulg]

I have read people are filling the corny then pressurising to 20 psi to seal the lid .I normally force carbonate.
My question is do you then release the pressure immediately or keep the corny pressurised allowing the gas to be absorbed .
I realise that I need to have only a few psi to serve (I an using a check valve and will set the regulator to as low as possible ,maybe 3- 4 psi.
My other question is is the cask breather option a better setup bearing in mind I take about 2-3 weeks to drink one corny.I have seen it stated that beer keeps ok with a cask breather ,I think maybe it was scooby although he was using proper casks
thanks in advance
Paul

[IPA]

I use 1 bar (14psi) to seal the lid. Then leave the beer/lager to carbonate naturaly ( add 80grms sugar) then keep the pressure at 1 bar to serve; Result clear beer and minimal gas usage. Regards to breathers as soon as air enters the beer will start to oxidise and will need to be drunk asap.

[hotmog]

Regards to breathers as soon as air enters the beer will start to oxidise and will need to be drunk asap.

A cask breather should be connected to a CO2 supply via a regulator set at around 5psi. As beer is drawn off, it admits the same volume of CO2 to replace it, thus maintaining atmospheric pressure within the cask (any additional pressure being vented off via a one-way valve). No air should, therefore, enter.

However I found that in practice, when using a cask breather with a cornie, the lack of positive internal pressure relative to the outside means that an airtight lid seal is difficult to maintain, especially where there is a less than perfect fit.The amount of negative internal pressure created when beer is drawn off is not constant, but reduces proportionately as the volume of the airspace above the beer increases. After about half-empty, I found that drawing off a pint could result in there being insufficient negative internal pressure created to open the inlet valve, which meant that the partial vacuum would instead attain atmospheric equilibrium over time by air seeping in through the compromised lid seal.

I no longer use a cask breather. Instead, with the lid in place but not clamped down, I first purge the airspace in a freshly-filled cornie with CO2, then shut the lid and give it a burst to around 10-15psi to ensure a good seal. Once connected up for dispense, I set the regulator to maintain a pressure of around 5psi.

[Kev888]

Yes cornies seal mostly by pressure, I've got quite a number and some of them don't need much to seal but some need at least several PSI to avoid gas leaks. I know that a few people can/do use theirs at very low pressure but personally with mine I'd consider it a path to frustration..

I looked into threads on casks and cask breathers recently. One thing I picked up on was a difference in the way people use the term 'condition'. If I'm interpreting correctly, use of a cask breather with CO2 and/or a demand valve will stop the beer 'oxidising' (assuming its in a vessel that doesn't leak or transmit oxygen), but it won't stop it losing 'carbonation' if the vessel is less pressurised when serving than it was at priming/storage.

Cheers
kev

[paulg]

thanks for the replies guys
hotmog
you have echoed my concerns reference lid sealing I currently have my beers force carbonated and then serve with a dalex tap at 5 psi.
I also have a beer engine and would like to use it ,currently it is set up with a check valve and I had the regulator as low as possible I think it was about 4 psi but I had previously force carbed the beer and it probably had too much co2 dissolved in the beer as it had been at 14 psi for quite some time and gave a lot of foam.
My current brew in the fermenter will be transferred to corny in a few days time and this is why I am asking these questions as i want to try the beer engine at the end of the month when I have house guests.
can i just clarify something you say you seal lid at 14 psi do you then drop the pressure or leave it and when you serve with 5 psi the extra pressure drops as you pull the first beers off I assume you are naturally carbonating not force carbonating

kev888
yes you are correct i think that the beer will lose condition ie amount of co2 dissolved in the beer if it is more than the pressure on top of the beer from the cask breather (1 atmosphere) I have seen it suggested that you can apply a higher gas pressure during the non serving periods using a valve to isolate the cask breather, and the breather will vent this off when you open the valve between the breather and the cask before serving .

another question
what about opening the pressure relief valve during the serving period and then at the end of the session repressurising the corny to seal the lid and then purging to expell any air from the keg.This would prevent the lid from not sealing but hopefully removing the air to slow down staling of the beer.A bit wasteful on gas I know

so the conclusion is cornies may be ok but you are better off with proper casks or polypins but if the corny seals ok at low pressure a breather or check valve set could work but you run the risk of air leeking past the lid seal.

[hotmog]

can i just clarify something you say you seal lid at 14 psi do you then drop the pressure or leave it and when you serve with 5 psi the extra pressure drops as you pull the first beers off I assume you are naturally carbonating not force carbonating

When I seal the lid at 14 psi it is generally another 3 or 4 weeks before the cornie is connected up for dispense. I don't prime, and depending on the amount of residual fermentation that takes place and the effectiveness of the lid seal (a couple of my "bargain" cornies from Norm have sustained a few knocks and can be difficult to get a tight seal on, even with 20 psi ), this can mean the internal pressure can vary tremendously by the time I come to hook it up to my beer engine - anything from zero to 20+ psi. It goes without saying, of course, that you need a check valve (otherwise known as a "demand" valve) in the beer line between the cornie and hand pump. Bearing in mind the very limited head space in a full cornie, a pressure even of 14 - 20 psi will diminish very quickly as a pint is drawn off, and it will usually need more CO2 injected when it's time for the second pint, so I don't normally vent it using the pressure relief valve unless absolutely necessary. You can tell if there is excessive pressure within the cornie because the check valve will make a knocking sound as the beer-pump handle is pulled.

another question
what about opening the pressure relief valve during the serving period and then at the end of the session repressurising the corny to seal the lid and then purging to expell any air from the keg.This would prevent the lid from not sealing but hopefully removing the air to slow down staling of the beer.A bit wasteful on gas I know

Once the lid is sealed, if it's a good fit then it should still be OK even if the internal pressure is dropped to, say, 5 psi. However it is difficult to generalise as it all very much depends on the particular cornie you are using. Some of mine, being of the "bargain" variety, have less than perfect sealing properties. What I tend to do with them is not to have the CO2 regulator permanently connected "on" 24/7 at 5 psi, as I cannot trust the seals not to leak and I could very quickly end up with an empty CO2 cylinder (it's happened to me before). So what I do instead is to keep the regulator valve off until I want to pull a pint, turn it on to charge the cornie up to 5 psi while I dispense my beer, then release it again. That represents a practical compromise for me that does not waste gas.

[newtonsshed]

I'm looking at doing something similar, I currently use a hand pump to a corny without any gas being connected as I currently only have empty c02 bottles that I just haven't got round to filling nack up and drinking a corny within 2 weeks
It's usually ok for the first week half way down the corny by the end whilst still drinkable not as fresh as the first half.
I'm thinking of replacing the black seals to the red seals which I understand are designed to seal at lower pressure which may suit if setting pressure to 4 or 5 psi would this help with a cask breather ?
Thanks
Andy

[paulg]

hotmog
once again thanks for answering my questions
I use the dont conect the gas 24/7 method on my dalex tap setup for the same reason although i normally find when I open the gas it dosnt let any into the corny so I assume the sels are pretty good.
I will try your method on my beer engine as i already have the thing setup with a demand valve and a secondary regulator marked in 1 psi units so should be able to set at 5 psi easily.
the only time I have tried the beer engine before was with a beer force carbed at about 14-20 psi and i got exactly the knocking sound you mentioned and lots of foam in my glass without using a sparkler (I am a southerner ,suffolk man at heart).
Although my beer engine has a swan neck spout,I would like to change it to a role over type tap but am not sure if it can be done as it is a worthside clamp on model and the taps are listed as for cabinet type angram pumps.
once again thanks
Paul