Carbonation Blues

[UsernameTaken]

As I think you all know by now I am new to kegging and am having carbonation issues.

To date I have under carbonated, over carbonated and taken over carbonated beer back to under carbonated without seeming to have ever hit the sweet spot on the way up or back!

I am running 2 kegs off the one regulator and aiming for a serving pressure somewhere between 12 and 15 psi based on what I have read.

I have 3 meters of 4mm line going from keg to picnic taps based on what the shop recommended.

My OC beer is way heady (80%+ of the glass) and my UC beer has a decent head (10 to 20% of glass) and whilst not being dead flat just does not have that effervescent carbonation quality we know and love!

All help and advice appreciated.

Except for that time someone said "Look it Up" that was neither helpful or appreciated...

Cheers,
UNT

 

[mtb]

Did you get your CO2 filled yourself? Or did you get the bottle already filled?
I ask because (and I've posted this in previous threads, because it bit me in the ***) pub gas bottles are often ~70% nitrogen. Nitrogen will do nothing to carbonate your beer.

 

[mofox1]

I've got about 4.5m of 5mm line serving at ~10psi, so without attempting to look up the line/pressure/temperature chart I would assume the serving pressure is too high for the line.

Other factors could be temp, dispensing unit or equipment faults. Temp should be relatively constant to avoid extra CO2 uptake at the lower temp. Also make sure that the temp is appropriate for the line setup. A picnic tap works for some, but I never got the hang of it. Try out a pluto gun and see how it goes. It could also be blocked (hop debris) or not fully opening ball lock poppets if one of the springs are far too stiff.

 

[Midnight Brew]

Do you open the tap into the glass and start pouring or do you let a little go into your drip tray.

What I mean is, if the taps are significantly warmer then the beer and line when you first open the tap you are going to get a big heady glass. If you 'tap off' a tiny bit (>50ml) then pour into the glass you'll get a decent pour. This is what they do at pubs and alike as they serve under high pressure with lines running to a cellar/fridge.

Just a thought before it comes down to line length, pressure and temperature. I cant count how many times my mates and family ask "How come you can pour a perfect beer but I cant?"

 

[UsernameTaken]

Full gas bottle purchased from highly reputable home brew supply shop.

Kegs, beer line and picnic taps all live in fridge.

Fridge at about 4c but opening and closing the door a lot changes this!

Planning door mounted taps once I get this all working, so pluto guns not an option.

Beer is pouring nicely into glass now with goo 10 to 20% head, just not a fizzy as most other beers I drink?

Cheers,
UNT

 

[Grott]

Do you open the tap into the glass and start pouring or do you let a little go into your drip tray.]

Your other advice was very good but ".........into your drip tray"? Like with hydro test samples, this must be consumed.

 

[Grott]

I take it that the beer isn't tasting flat? So your happy with the head you pour but lacking bubbles in the glass? Depending on carbonation time the bubbles can be quite small, hold the glass up to the light and have a good check. Secondly, when the head has gone swirl the glass to check for a slight head forming as co2 comes out of solution.

 

[UsernameTaken]

The beer is tasting flat. Not dead flat, but flat non the less!

UNT

 

[Chap]

I'm also new to kegging, I'll tell you what I've done and it may or may not help:
36psi for 36 hrs, bit of a shake for 20 sec, rest for 10, shake for 20, wait 5 minutes, remove gas, release prv, attach gas and drop to 8psi serving pressure.
Fridge tap, 4 feet of 5mm ID beer line, tap is about 300mm above top of keg. Pouring well, good head, little undercarbed. Next beer will increase to approx 10psi and see what difference it makes

 

[UsernameTaken]

What I am struggling with is identifying whether it is under or over carbed?

I get that flat with no head is under and 70%+ head is over!

However, slightly flat beer with decent head confuses me!

Is that under or over?

Cheers,
UNT

 

[Chap]

Having next to no knowledge on the matter, i would say under. You need more CO2 in the solution and lower serving pressure to compensate. Leave at the current pressure for a couple to a few days then drop a couple to a few psi to serve.
Disclaimer: this is all a big guess from the limited knowledge I have read across the forum and elsewhere. Hopefully the experienced keggers come up with a solution

 

[Danscraftbeer]

What I am struggling with is identifying whether it is under or over carbed?

I get that flat with no head is under and 70%+ head is over!

However, slightly flat beer with decent head confuses me!

Is that under or over?

Cheers,
UNT

Try turning down the serving pressure. What beers that you compare to are you talking about? Most mega swills are highly carbonated but dry and thin bodied so they have minimal to no head so you can fill to the top of patrons glasses so they don't feel their getting ripped of with an inch of froth. What is your home brew final gravity? Most home brew has more body than common mega swills that gets more head and can feel less carbonated.
The failsafe way to carbonate is set it at say 12psi and leave it for a week. You cant go wrong that way.

 

[Danscraftbeer]

You may just prefer thinner bodied beer. So aim at beers to finish gravity at say 1.006. I've finished as low as 1.002 as a low carb beer and you can definitely get higher carbonation with beer like that with lower head and practically no head retention etc. Once its fully carbed you can turn down the serving pressure to say ~7psi and get fully filled glasses. Its just a slower pour.

 

[UsernameTaken]

My IPA's finish around 1.012 and my Mid Strength Pale Ale finishes at 1.018 as intended with the low attenuation Windsor yeast.

I was getting better carbonation when I was bottling these same beers!

Cheers,
UNT

 

[Danscraftbeer]

Yeah it still confuses me a little after years of kegging. I have a Porter that was supposed to finish at 1.018 instead it finished at 1.010. It still has good body. It seems much more body than I expected with a low FG. I Oaked it in the keg with baked Oak chips that seem to add to body as well. It seems lower in carbonation than the Pale Ales even though its been connected to 12psi for 3 weeks now. Its like it gets to a level of carbonation saturation and cant seem to get carbed up any more. I accept that's the character of the beer and I shouldn't try to force carb it anymore. I have done in the past and just spoiled the beer as in too frothy!


Another thing is why I suggested lower serving pressure is because all that excessive froth is released carbonation. If you get a glass of mostly froth the beer is flattened by excessive release of the co2. It takes time with your own set up to fine tune a balance.
Eg; Cold enough and slow enough to retain the carbonation when served, and server skills too as mentioned.
If visitors drink my beer I have to serve it. They stuff up serving themselves a glass every time haha.

 

[Brewnicorn]

Besides the expense, I'll happily admit that the idea of spoiling some hard work brewing by over/under carbing or pressurising a keg scares me off the idea a bit.
And I'll admit I'm a total novice with zero understanding in this area. I do read about it a bit on here and I've watched YouTube videos. I guess it's not the only imperfect science in brewing.

 

[Danscraftbeer]

Not actually spoiled beer but some wastage losses that hurts.
I say go for the no fail option again. Set and forget. 12psi, 4 degrees Celsius for a week. That's it. Cant go wrong.
Or the impatience is the true fail. To try and force carb faster with all these crank up pressure, shaking and all. Forget all that its far to open for mistakes and then you probably pull your hair out for longer than a week doing all sorts of other crazy stab in the dark techniques to try and fix the previous crazy stab in the dark techniques that got you in trouble in the first place.

But then again every brewer, kegger must have to do this, (been there done that) with these things in trial and error learning anyway usually.

 

[UsernameTaken]

Ok, I clearly did not fully understand the role of serving pressure. Just checked both kegs again after purging and resetting to 8psi and leaving for 20 hours.

Both kegs are now pouring beautifully. Good head and nice carb - super happy!

I was stupidly thinking if the carb was a bit low I should bump up the serving pressure. But I now realise that was making it even worse.

12psi for 7 days and serving at 8psi for life now!

Thank you all very much for your patience, support and advice...

...except for the person who told me to look it up. They were no help at all!

Cheers,
UNT

 

[Danscraftbeer]

Just to re add. 12 psi all the way works for me. I rarely adjust the reg ever because I have three 18l kegs and a 11lt keg all connected to the same line. If any keg seems a little over carbed I just disconnect the gas line and serve it under its own decreasing pressure. Then no Co2 wastage etc. You could release a bit of pressure but that's a waste etc.
This technique works fine. When this keg wont pour anymore I just connect the line again for a second and disconnect again, to re pressurize a bit enough to pour. This is the easiest fix for over carbonated kegged beer in my experience. This is simpler and less fussing to correct the problem without disturbing the keg but I rarely ever get the problem any more as will any brewer.

 

[UsernameTaken]

Ok, maybe I spoke too soon. A few pints later and I'm loosing carb again, so maybe 12 and not 8 is the sweet spot for my psi!

Will reset and report back in 24 hours?

Cheers,
UNT