Cask to Beer Engine - pressure

[Jim]

So I've got my BE linked to my pub cask. As I'm using a cask breather spigot to keep the air off the beer, I've included a demand valve in the beer line to stop beer being forced through the BE when not in use. However, the valve is disturbing the beer flow and causing foaming (manageable but not ideal).

So here's my plan; I take the demand valve out and therefore must make sure that the pressure in the cask is insufficient to lift the beer as far as the spout of the BE. My calculations show that even a very slight pressure (1 psi) would lift water about 27" (beer slightly less as it's heavier, say 25"). So it seems the usual pressure provided by a cask breather of about 4psi would push the beer straight through a BE unless it was about 9 feet above the cask! Mine is only about 2 feet above.

I'm assuming the weight of 1 cu in of water is about 0.036 lbs, therefore each psi of pressure will lift it 1/0.036 inches, which is 28".

Have I got this right??

[Brighteyebeer]

Hi Jim
I don't use casks - I have a corny type keg, but mostly dispense from PBs, adapted to function as kegs, with 3 or 4 psi going into them from a cylinder (straight through - no demand valve). My BE drips prodigiously! BUT I stop the problem by putting a shut-off valve between the 3/8 beer line and my non-return valve. Open it to pull a pint, then close it before the glass fills, and empty the BE cylinder with the last pull. Not essential to empty the cylinder - closing the shut-off valve holds the pressure back, and stops the drips (well, more of a stream than a drip!). Simple but effective!
Cheers, Chris

[leedsbrew]

Hi Jim
I don't use casks - I have a corny type keg, but mostly dispense from PBs, adapted to function as kegs, with 3 or 4 psi going into them from a cylinder (straight through - no demand valve). My BE drips prodigiously! BUT I stop the problem by putting a shut-off valve between the 3/8 beer line and my non-return valve. Open it to pull a pint, then close it before the glass fills, and empty the BE cylinder with the last pull. Not essential to empty the cylinder - closing the shut-off valve holds the pressure back, and stops the drips (well, more of a stream than a drip!). Simple but effective!
Cheers, Chris

yep, same system here!

[Jim]

Hmm, sounds like I might as well leave the demand valve in and put up with the slight foaming.

Are there any pros about that have experience of using cask breathers commercially? How does that work?

[boingy]

This sounds to be the perfect excuse to dig a cellar, Jim. Just think about all that unexploited man-space beneath your floor....

Two ideas:

1. Does the breather valve have to be driven at 4 PSI?
2. Can you "balance" the system by using a long length of 3/16 beer line like we do with cornies?

(And the engineer in me wonders if a beer engine could be modified such that it acts as a shut-off valve when it's in the "home" position)

[paulg]

I have no experience of a cask breather yet but was under the impression that they supplied co2 at atmospheric pressure on the cask side so should not pressurise the system.In put gas pressure up to say 6 psi ,output only activated when vacuum occurs in the cask and if pressure in cask rises above 1 atmosphere due to gas coming out of solution it is ventilated.
Is your pin higher than your beer engine jim?.This would cause the beer to put pressure on the beer engine by gravity.
I ask as I currently have a beer engine connected to corny kegs with demand valve fitted and planned to remove it when I get my pins and cask breather next week .I am trying at the moment to track down a co2 leak on my regulator setup before i switch to the new system

[Jim]

I have no experience of a cask breather yet but was under the impression that they supplied co2 at atmospheric pressure on the cask side so should not pressurise the system.In put gas pressure up to say 6 psi ,output only activated when vacuum occurs in the cask and if pressure in cask rises above 1 atmosphere due to gas coming out of solution it is ventilated.
Is your pin higher than your beer engine jim?.This would cause the beer to put pressure on the beer engine by gravity.
I ask as I currently have a beer engine connected to corny kegs with demand valve fitted and planned to remove it when I get my pins and cask breather next week .I am trying at the moment to track down a co2 leak on my regulator setup before i switch to the new system

You might well be right, as I'm just going on memory of stuff I've read about cask breathers being set at about 3 or 4 psi. HOwever, if they hold the cask at atmospheric all the time and vent excess pressure they'd need to be shut off while the cask wasn't in use otherwise the beer would lose all it's condition over the course a few days. Even when using spiles you have to stick a hard spile in between sessions.

Boingy, I'll apply for planning permission for a cellar in the meantime.

[Jim]

Maybe I should've searched the forum!

viewtopic.php?f=6&t=35629

[steambrew]

I use a cask asperator on my pins with the co2 set to I psi with 3 /4 metres of 3/8 pipe coiled in a circle to my beer engine ,is 2ft above my pin and a non return valve and demand valve from A1 Barstuff and after getting a selection of angram nozzles trial a error proved a hit no problems a good pint every time

[Jim]

......Is your pin higher than your beer engine jim?.........

No. The spout of the BE is about 2 foot above the top of the cask (so about 28" above the top of the beer, which means just high enough for 1psi to be OK).

Steambrew, you've just confirmed that breathers/aspirators are set to about 1 psi (or sometimes a bit less).

I was just thinking before that the breather probably also acts as a one way valve - is that correct? If so, it wouldn't vent all the pressure out of the cask, but would just replenish what is taken out, and the pressure would be able to build up again between sessions, preventing the beer going flat.

[steambrew]

Yes Jim you are correct , some time ago my local we're putting good beer down the drain ,I suggested my system they fitted it no more beer down the drain Camera have a problem with it

[SiHoltye]

I had a 3/8 inlet on my check valve inlet then half inch braided out to BE. Experienced the foaming so replaced the check valve with a 15mm inline plumbing check valve. Incorporated in the line by adding copper stubs to the compression ends of the valve, then push fit to hose tails to connect the copper ends to the hose. Run only one pin so far but perfect results, no excessive foaming and works great with a sparkler for a creamier head.

[leedsbrew]

I had a 3/8 inlet on my check valve inlet then half inch braided out to BE. Experienced the foaming so replaced the check valve with a 15mm inline plumbing check valve. Incorporated in the line by adding copper stubs to the compression ends of the valve, then push fit to hose tails to connect the copper ends to the hose. Run only one pin so far but perfect results, no excessive foaming and works great with a sparkler for a creamier head.

Any chance of a pic fella?

[will_raymo2000]

As far as I'm aware from my dealings with my cellar technicians it's not possible to adjust a cask breathers output pressure, plus they only work when a vacuum is formed by the hand pump, replacing cellar air with co2. So if your beer engine doesn't leak when the cask is naturally aspirated why should it leak when a cask breather is attached?

Greene King, who look after my cellar (even though we are a freehouse) have set the input pressure on a secondary regulator to 10psi if that's any help?

[darkonnis]

You could put a valve between the aspirator and the cask and just leave it half closed, though how much of a pressure drop you'd get is debatable and would be trial and error.