Serving Pressure In Keg As Volume Decreases

[BobtheBrewer]

Do any other brewers have this problem because I can't believe it only happens to me. I use 18/19 litre kegs, and can get a great pour for about three quarters of the keg. Then the head keeps growing and growing. I have tried lowering the pouring pressure without any noticeable result. Is there a fix for this?

 

[Lord Raja Goomba I]

I have this trick of dropping it back to 40kpa (which is about half my calculated pressure for an APA/AIPA). Release the headspace in the keg, and let it fill at 40. Drop it to zero, and pour. Once you struggling to get decent pressure, ramp it back up to 40 kpa, let it fill, then ramp down to zero again, and I tend to get the right head (so long as I pour well) every time - right to the bottom of the keg.

I was struggling for a long time with 3/4 head in the glass. This seems to be a good technique for my system.

 

[BobtheBrewer]

I have this trick of dropping it back to 40kpa (which is about half my calculated pressure for an APA/AIPA). Release the headspace in the keg, and let it fill at 40. Drop it to zero, and pour. Once you struggling to get decent pressure, ramp it back up to 40 kpa, let it fill, then ramp down to zero again, and I tend to get the right head (so long as I pour well) every time - right to the bottom of the keg.

I was struggling for a long time with 3/4 head in the glass. This seems to be a good technique for my system.

Thank you LRG. I can't believe it took me 9 years to ask this question.

 

[Bongchitis]

Thats strange. You would think if the headspace and the gas in the beer had reached equilibrium then there would be no change at all. I must say I have never had such a problem. Whats your carb pressure? Do you drink your beer quickly after kegging?

Just doesn't make sense to me.... but either does Lady Gaga and look how popular she is.

 

[glenwal]

Your serving pressure is to high, it needs to be balanced to your carb level. Your first half of the keg its ok because or hasn't had time to properly carb yet because you are force carbing. Lowering the pressure half way through a keg won't decarb the beer that's in the keg instantly unless you shake the keg and release the excess pressure.

 

[pcmfisher]

Is it only the first half a pour that is heady?
If you pour another straight away is it better?
Do you leave your gas on all the time or just turn it on when the pour slows down?

Lowering the pouring pressure may appear to make it better in the short term but will probably make it worse.
You must have enough head pressure to keep the amount of gas in solution or you will have bubbles forming in your beer line which will give you a shitty pour. You must also have long enough beer lines to compensate for this pouring pressure.
If your system is balanced you should not have this problem.
Cheers

 

[stux]

Sounds to me like your system isn't balanced.

With flow controllers my pouring pressure *is* my carbing pressure and then I can use the flow controller to adjust the head. Remains constant for whole keg