First time serving from my Fermentasaurus keg and only getting foam :-( I have it pressurised to about 12 PSI at the moment and have 3 metres of 3/8 beer line connected to a tap. All I get from the tap is foam and the beer line is not filling up with beer! It comes out is spurts, I can see big gaps in the beer line presumably filled with gas. What am I doing wrong? I thought this was all correct, a few metres of beer line and a tap and pressuring to around 10-15psi
how to serve from keg - only getting foam!
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What you need to do depends on the beer.
If you’re serving a stout, bitter, mild or beer with similarly low carbonation the pressure is too high and turning down the pressure to about 8psi will ease, maybe eliminate, your problem. You may have to also vent the keg with the gas turned off in order to release some of the CO2 from the over-carbonated beer. To do this turn off the gas, pull the PRV to depressurise the keg, leave it for a few minutes for more CO2 to come out of solution, pull the PRV again, turn on the gas.
If you’re serving an IPA or something that needs a bit more carbonation you need to leave the pressure higher but you need to increase the resistance of the beer line by using a length of 3/16 line. The length will depend on the pressure you need for the carbonation you want.
Gas in the beer line might indicate the beer line is warmer than the keg (encouraging CO2 to be released from solution in the beer line), or may indicate an infection in the beer line (make sure you clean the lines regularly), or perhaps is the result of a leaky seal (the most unlikely but possible if the keg is old, an o-ring is damaged, or you’ve stripped it down and not got it reassembled correctly).
If you’re serving a stout, bitter, mild or beer with similarly low carbonation the pressure is too high and turning down the pressure to about 8psi will ease, maybe eliminate, your problem. You may have to also vent the keg with the gas turned off in order to release some of the CO2 from the over-carbonated beer. To do this turn off the gas, pull the PRV to depressurise the keg, leave it for a few minutes for more CO2 to come out of solution, pull the PRV again, turn on the gas.
If you’re serving an IPA or something that needs a bit more carbonation you need to leave the pressure higher but you need to increase the resistance of the beer line by using a length of 3/16 line. The length will depend on the pressure you need for the carbonation you want.
Gas in the beer line might indicate the beer line is warmer than the keg (encouraging CO2 to be released from solution in the beer line), or may indicate an infection in the beer line (make sure you clean the lines regularly), or perhaps is the result of a leaky seal (the most unlikely but possible if the keg is old, an o-ring is damaged, or you’ve stripped it down and not got it reassembled correctly).
The line was at room temp and the beer at 2.8 degrees so there was a massive difference in temp! Its a Pale Ale so wanting a bit more carbonation that a stout or bitter. Maybe I should try again now the line has had an hour or so to cool down? Although now Im trying to warm the beer up, the temp in the fridge is high as the heater is on and the thermometer is in the beer thermowell - guess I just need to leave it a few hours and try tonight when its a bit more balanced
I think you’re going to need 3/16 beer line to solve the foaming issue but certainly that kind of temperature differential will cause gassing in the beer line as well.
I’d say use 4m of 3/16 to start, get the carbonation you want, then cut short lengths (10cm) from the beer line until you get a good flow rate without too much foaming.
I guess you have a floating dip tube then? Did you weigh it down with a SS nut or similar? It is a fairly common issue that the inlet to the dip tube floats on the surface and sucks in the CO2 from above the beer, you should be able to see if this is happening when you pull a pint off it.
This has certainly been my experience. I tried 5/16" (actually in my case 1/4" but it's as near as dammit) and it didn't work.
The key, as @foxbat says, is to reduce the flow rate. Fast flow rate is your enemy, because when a fast flow goes through the constriction in the tap it causes a local pressure drop (Bernoulli principle) that knocks all the CO2 out of solution and causes foaming.
The secret with the 2m x 3/16" line is that the friction is much higher and it slows the flow rate down over a much longer distance i.e. no localised pressure drop.
No.
At least two metres of this (buy lots, it's cheap):
https://www.themaltmiller.co.uk/product/316-beer-line/
And two of these for the ends to bring it back to 3/8" (they push into whatever you're currently pushing your 3/8" beer line into at each end). Hopefully not barbed connectors....
https://www.themaltmiller.co.uk/product/john-guest-3-8-stem-x-3-16-pushfit-reducer/
As an extra bonus 3/16" line is much easier to bend and route around where you need it to go than 3/8".
+1 to this. I now use 3/16 for gas line too for this very reason. Sooooo much easier to manipulate!
Yep - good for feeding CO2 into a fridge via the drain hole, too.
Yep me too.
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For 5/16 line you need about 51 feet so 3/16 is what you need. I've got 3m/10ft of 3/16 and though it runs very slow it doesn't foam up and I get a nice head. Been thinking about trimming it down a few cm or so to see if I can get it to run a bit quicker.
Looks a decent pint. Would I be right to think you reduce pressure for serving?
Just for the benefit of the OP, to serve at carbing pressure (as is my preference as I don'tthen have to change the regulator setting), either flow control or 3/16 would be required.
