Pouring Flat Beer / All Head

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Wimmig

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Hey everyone, i've got a problem pouring what seems to be flat beer, and all head. It has me very confused. The reg is set at 11psi (coopers pale, correct if wrong please). Lines are kink free, and have no bubbles in them.

Pours mostly head, but by the look of the pour it seems the co2 is not saturating the beer. If i was pouring a hefeweizen then the head would be great (you could build a small house on it). As i'm not this is clearly a problem. The only thing i can think of is that the tap is leaking at the join, allowing oxy in the one way valve and into the beer.

Any ideas?

Cheers
 
Sounds like it might be over-carbed. What's the temp of the keg, length and size of beer line?
 
Sounds like it might be over-carbed. What's the temp of the keg, length and size of beer line?

Current temp is 3c (+/- 0.5). Off the top of my head i don't know the ID of the beer line. It is long (~ 1.5m - 2m). Commerical coopers keg.
 
From the articles in the link at the top

FOAMING PROBLEMS


If you've followed these pointers, you really shouldn't have problems with excessive foaming. Foaming is caused when the dissolved gas comes out of the beer, forming bubbles in the process. This happens to a certain extent whenever we pour a beer, which is why we get a head - but if we're not careful we can cause it to happen too dramatically and we get far too much head (excessive foaming) and flat beer. This happens when the beer warms up (for example, the first beer coming through a warm tap), or the pressure drops (for example, if you've reduced the keg pressure to slow down the rate of pour). It can also happen if the tap you are using was not designed for beer, or if it wasn't open all the way (beer taps are either open or shut - there is no in between!) It can also be exacerbated if the beer encounters any turbulence on its way through the line. For this reason it is best to keep any joins or line diameter changes to a minimum, leave the fridge thermostat and the regulator alone, and insulate any line that is outside the fridge.

If you have inadvertently overcarbonated a keg, then you will nearly always get excessive foaming unless you can increase the pressure to a level which can keep the gas in solution, and increase the serving resistance to a level that allows a controlled pour. In this case you will simply get a very gassy beer (and probably a large head), but hopefully it will be drinkable.

Generally though, you will need to vent an overcarbonated keg and allow the excess gas to escape from the liquid. This can be done by simply disconnecting the gas, releasing the pressure valve, giving the keg a shake, then releasing the valve again and so on. Each time you do this you will get another burst of escaping gas (and probably foam), which has all come out of the beer. Shaking increases the surface area of the liquid and assists gas to pass out of the beer into the lower pressure of the headspace (it also helps when trying to get gas into the beer, the only difference being whether the gas pressure in the headspace is higher or lower than the beer's current 'equilibrium' point. If it is exactly equal then shaking a keg will have no effect).

Ultimately you want to reduce the excessive carbonation to just BELOW your target level, so that when you reconnect the gas at your equilibrium pressure the beer will be in 'absorbing' mode which, as we know, causes no foaming problems - unlike beer which is in 'expelling' mode.

It is, of course, better to avoid overcarbonating the keg in the first place, and the best way to do this is to...

STOP SCREWING WITH YOUR REGULATOR!
 
That temp and pressure should have it at around 2.5 volumes of co2.....however, there are other variables apart from line length:

The ID of the line
height of the tap above the centre of the keg
temperature of the tap

And thats just assuming that the carbonation is actually what that pressure/temp combo will give you. Variables on that are:

Method of carbonation (ie force carbed, slow carbed, or primed?)

If it was slow carbed at serving temp (or forced carbed at serving pressure and serving temp), then it is a line balance issue. Either too short a line for the ID/height, or a warm tap (warm tap would give initial foaming, but subsequent pours should be OK).

If it was force carbed above serving pressure (or at a lower temp), or it was primed, then it could be either a balance issue, or overcarbed. Or both.
 
Thanks everyone. I dialed down the reg output, then slowly brought it back up in line with the new keg pressure. Currently at around 5psi (1.5c) and is perfect. Excellent co2 saturation and head retention.

Cheers!
 
Hi All,

been reading through alot of info. wathing alot of youtube videos. Im only new to kegging and put my second beer into a keg now. both have been carbonating for over a week. and now im having this same issue.
when i pour it, all i get is head. ive tried dialing back the PSI and working it back up.
thought i had it right then went back for another one and back to all head. It does settle and give a nice beer to drink.. but im not sure what else to do at this point.

Any advice or tips to check would be muchly appreciated.
TIA.
 
Its a common enough problem.
What you need to do is to measure the temperature of the beer (well the temp of water in a glass in the fridge will do) and then note the pressure.
The amount of CO2 dissolved in beer is directly related to temperature and pressure, so at a given temperature and pressure the amount of dissolved CO2 is know.
Say your fridge was at 3oC and you had 150kPa of pressure, look at a carbonation table (or an online calculator, write a spreadsheet...)
From Braukaiser
1608675352217.png

The 3 in the left hand column is the temperature, go along the pressure row to 150 (1.5*100=150kPa), come down to where the two meet and you will see that you have 7.1g/L of dissolved CO2.
Thats around what you would need for a Hefeweizen but its getting close to double what you want for a Pale Ale (there are some recommended ranges on the bottom of the table).

The first step is to decide how much fizz you want (dissolved CO2). Second is to create the temperature and pressure conditions that give that level of dissolved CO2. Third is to configure you system so it pours well at the conditions you want. That's line length and diameter, type of tap... what is called creating a balanced system.

I only work in metric so if you ask more questions put the units in something rational, all the maths that underpins how this works is done in metric then converted to silly non system, its good to avoid being sillier than necessary.
Mark
 
Its a common enough problem.
What you need to do is to measure the temperature of the beer (well the temp of water in a glass in the fridge will do) and then note the pressure.
The amount of CO2 dissolved in beer is directly related to temperature and pressure, so at a given temperature and pressure the amount of dissolved CO2 is know.
Say your fridge was at 3oC and you had 150kPa of pressure, look at a carbonation table (or an online calculator, write a spreadsheet...)
From Braukaiser
View attachment 119690
The 3 in the left hand column is the temperature, go along the pressure row to 150 (1.5*100=150kPa), come down to where the two meet and you will see that you have 7.1g/L of dissolved CO2.
Thats around what you would need for a Hefeweizen but its getting close to double what you want for a Pale Ale (there are some recommended ranges on the bottom of the table).

The first step is to decide how much fizz you want (dissolved CO2). Second is to create the temperature and pressure conditions that give that level of dissolved CO2. Third is to configure you system so it pours well at the conditions you want. That's line length and diameter, type of tap... what is called creating a balanced system.

I only work in metric so if you ask more questions put the units in something rational, all the maths that underpins how this works is done in metric then converted to silly non system, its good to avoid being sillier than necessary.
Mark

Thanks for the info MHB, im thinking its the temp after reading through this. its a home made unit, but its giving me diff temps. the temp control unit wont go below 15c. the external thermometer i got in through the back wont go below 20~c .. yet i got a batch brewing in there and the temp sticker on the side of that is sitting around the 14-16c which is perfect for the stout im doing..
So just done the glass of water trick you mentioned above. let that sit for a while an see what that does. other wise. think i may have to build the keezer which is on the cards. was just hoping not so soon..
 
Thanks for the info MHB, im thinking its the temp after reading through this. its a home made unit, but its giving me diff temps. the temp control unit wont go below 15c. the external thermometer i got in through the back wont go below 20~c .. yet i got a batch brewing in there and the temp sticker on the side of that is sitting around the 14-16c which is perfect for the stout im doing..
So just done the glass of water trick you mentioned above. let that sit for a while an see what that does. other wise. think i may have to build the keezer which is on the cards. was just hoping not so soon..

so what your saying is you have a beer on tap + a beer on fermanting and becuase you have set your temp unit to 15 degrees you cant serve beer at the normal serving temp?

for set and forget you can use the keg-king carb chart which is similar to what mhb put in his post
KEGKING-Set-Forget-CO2-Carbonation-Chart.png



might be useful if you can't get below 15°c
 
so what your saying is you have a beer on tap + a beer on fermanting and becuase you have set your temp unit to 15 degrees you cant serve beer at the normal serving temp?

for set and forget you can use the keg-king carb chart which is similar to what mhb put in his post
View attachment 119720


might be useful if you can't get below 15°c
I may be wrong but serving at 15c would mean about 20PSI. And then the co2 is more likely to get knocked out of solution like a warm bottle of soda water. Which would mean more head.

So in theory the colder the beer the less PSI and the more likely to "keep its fizz" then again that may be incorrect.
 
so what your saying is you have a beer on tap + a beer on fermanting and becuase you have set your temp unit to 15 degrees you cant serve beer at the normal serving temp?

for set and forget you can use the keg-king carb chart which is similar to what mhb put in his post
View attachment 119720


might be useful if you can't get below 15°c
so what your saying is you have a beer on tap + a beer on fermanting and becuase you have set your temp unit to 15 degrees you cant serve beer at the normal serving temp?

for set and forget you can use the keg-king carb chart which is similar to what mhb put in his post
View attachment 119720


might be useful if you can't get below 15°c

Hi Devil,
it would seem the home made keg fridge i bought with all the gear i needed to start isnt getting down to temp. the lowest it is getting is around 18-22c.. which going through the table as you supplied aswell as MHB. its pretty useless unless i wanna keep a wort around them temps.

I got my other fridge out of storage today and have that running at moment, its pulling down to 7-8c which is much better as i enjoy cold beer.. not warm.

looks like ill be drilling some holes tomorrow and putting in some taps to pour some nice cold beers for xmas afterall.
hopefully this fixes my problem.
Appreciate everyones comments and the tables. they will definatly come in handy for other beers.

Will update tomorrow on how its going once i fit it all up.
Thanks again.
 
Hi Devil,
it would seem the home made keg fridge i bought with all the gear i needed to start isnt getting down to temp. the lowest it is getting is around 18-22c.. which going through the table as you supplied aswell as MHB. its pretty useless unless i wanna keep a wort around them temps.

I got my other fridge out of storage today and have that running at moment, its pulling down to 7-8c which is much better as i enjoy cold beer.. not warm.

looks like ill be drilling some holes tomorrow and putting in some taps to pour some nice cold beers for xmas afterall.
hopefully this fixes my problem.
Appreciate everyones comments and the tables. they will definatly come in handy for other beers.

Will update tomorrow on how its going once i fit it all up.
Thanks again.

Fridge seems to be set up for fermenting and not serving at those temps.
 
Fridge seems to be set up for fermenting and not serving at those temps.
its weird cos it was set up befor i bought it all and the beer and ginger beer use to come out great. so unless the fridge unit on it has lost gas or something while ive moved. Not sure.

Update though, have put the keg in a fridge an got it down to 4c with a external thermometer. beer is coming out pretty good. but still a bit too much head. only set at 6PSI. But in saying that , the beer tap is a trigger squeeze and unless you squeeze it real quick you get lots of head. so once i get taps set up i think it will be much better.
 

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