Air bubbles inside tap?

[dsaavedra]

I just set up a kegerator with 4 Intertap flow control faucets and have 2 beers on tap, so I'm still relatively new to dispensing from taps.

What I'm experiencing is slightly foamy first pours (~1/2 glass of foam) with the flow control set to ~50%. I can chalk this up to warm taps. Second pours, while the tap is still cool from the first pour, are usually better.

But I can also hear what sounds like air bubbles trapped inside the tap, it makes a kind of squirty/sputtering noise as beer flows from the faucet. Kind of like the noise you'd hear in a siphon if there was a bit of air in the line or a pump that is still purging air. Is this normal? I'm wondering if this is contributing to the foamy pours I experience?

 

[JONNYROTTEN]

That's air being sucked in. Not what you want. Sometimes it goes beer/foam/beer/foam as your pouring. Disconnect and reconnect the tap for starters. could be a bad connection. Purge the keg also and see if it helps.

 

[dsaavedra]

No air bubbles in the line so I'm not sure if its air getting sucked in. I should note that the flow control is set to ~50% (in an effort to reduce foam).... i'm wondering if this restriction is actually causing the beer to move faster through the tap (vernouli principle and all that) and causing what I'm experiencing.

Whatever it is, its definitely happening inside the faucet somewhere because each time I hear a bubble "squirt" through I can feel it very subtly through the tap handle.

 

[homebrewer_99]

OK, you are causing your problem. Taps work better fully open. Try this: Turn the CO2 off and dial down to 0 psi. Purge the CO2 from your tank. Turn your CO2 on and dial it to 2 psi. Allow a couple of seconds to fill in the void in the keg. Open your tap ALL THE WAY. The beer should start flowing. Now, SLOWLY (tick, tick, tick...) add psi (turn the screw) until it starts pouring the way you like it. Then stop turning the screw. You should be dialed in pretty good at that point.

 

[dsaavedra]

OK, you are causing your problem. Taps work better fully open. Try this: Turn the CO2 off and dial down to 0 psi. Purge the CO2 from your tank. Turn your CO2 on and dial it to 2 psi. Allow a couple of seconds to fill in the void in the keg. Open your tap ALL THE WAY. The beer should start flowing. Now, SLOWLY (tick, tick, tick...) add psi (turn the screw) until it starts pouring the way you like it. Then stop turning the screw. You should be dialed in pretty good at that point.

Interesting.... I wondered if this was the case. I'll try what you recommended about killing the CO2 pressure and slowly dialing it back up and see what happens. Wouldn't there be a risk of undercarbed beer if the pressure that ends up pouring well is less than the desired pressure per carbonation chart?

That just makes me wonder what is the point of flow control faucets if they cause problems when not at 100% flow? Is there a sweet spot or something? I filled a couple bottles using the flow control by dialing it down to a trickle and pouring down the side of the bottle, that seemed to work very well almost no foam and none of this squirty air bubble inside the faucet situation. It seems weird that putting the flow control at 50% would cause foam and trapped bubbles.

 

[day_trippr]

Wouldn't there be a risk of undercarbed beer if the pressure that ends up pouring well is less than the desired pressure per carbonation chart?

That's not a risk, it's a guaranteed outcome.
I'm wondering if hb_99 understands the flow control is separate from the faucet lever...

Cheers!

 

[homebrewer_99]

Yes, I do understand. Over-carbed beer and over-pressurized kegs produce foam.

You need to reduce the pressure in the keg.

 

[myndflyte]

So what happens when you open the flow control up to 100%? Is it foamy, flow too fast, etc? Is there a reason why you're just at 50%? Do you have shorter lines or just decided to go with 50% to start with?

 

[dsaavedra]

So what happens when you open the flow control up to 100%? Is it foamy, flow too fast, etc? Is there a reason why you're just at 50%? Do you have shorter lines or just decided to go with 50% to start with?

I am running shorter lines, I think they are 5 feet (they're the lines that came with my old picnic tap setup). If i have the flow control at 100% it pours a bit fast but i dont think it's anything catastrophic. I've mostly been pouring 5oz at a time so that i get more opportunity to fool with the faucets and at 100% is a little fast for filling small glasses. I'll pull a pint at 100% later and let you know.

I think another part of the problem is my faucets are getting warm between pours (its just me drinking the beer so theres some time between pours) leading to an initial spurt of foam on almost every pour. But i dont think this explains the air bubbles inside the faucet that i can hear/feel.

Finally, one of the kegs that was pouring with air bubbles ended up kicking while i was doing test pours, and i think the other one is very nearly empty. Is it common for kegs to get extra foamy as theyre nearly empty? I dont recall this from my picnic tap setup. I have one keg thats full and i can hear bubbles on this one too but it doesnt seem as bad.

 

[dsaavedra]

Here is a video with audio where you can hear the air bubbles inside the faucet with the flow control at ~50%. At first a whole bunch of foam comes out, which I guess is from the faucet being warm (hasn't been poured since last night). Then the beer clears up for a second or two and then you can hear air bubbles squirting through the faucet, accompanied with foam in the pour. This pint ended up being about ~75% foam.

 

[Kegtron]

Sounds like there are several possible issues going on here. A few thoughts:

- Longer lines almost always help, but a flow control faucet dialed back is equivalent to adding more length to your lines
- Warm lines & tap faucets will make the first pour foamy, but subsequent pours should be OK. If you pour a full pint and then 2nd pint is fine, this is your problem. If the 2nd pint is still foamy, you have other issues
- Even with perfectly balanced lines, you can get very foamy pours if your keg is over-carbonated. If your temperature/pressure ratio is not ideal, this will get worse as the keg level gets lower. Sounds like you're seeing this.

We wrote up an extensive guide to finding & fixing foaming with more details on the topics above:
http://www.kegtron.com/foam-sucks/

HTH,
-Steve

 

[dsaavedra]

Sounds like there are several possible issues going on here. A few thoughts:

- Longer lines almost always help, but a flow control faucet dialed back is equivalent to adding more length to your lines
- Warm lines & tap faucets will make the first pour foamy, but subsequent pours should be OK. If you pour a full pint and then 2nd pint is fine, this is your problem. If the 2nd pint is still foamy, you have other issues
- Even with perfectly balanced lines, you can get very foamy pours if your keg is over-carbonated. If your temperature/pressure ratio is not ideal, this will get worse as the keg level gets lower. Sounds like you're seeing this.

We wrote up an extensive guide to finding & fixing foaming with more details on the topics above:
http://www.kegtron.com/foam-sucks/

HTH,
-Steve

Thanks for the advice, I'm going to check out that article you linked after I finish this message - just skimming the section headers it looks great.


I think the issue I'm experiencing is over-carbonation because I can see air bubbles in my beer lines, which I assume is causing the foam and bubbly noise through the faucets, not air trapped in the actual faucet.

I when I first set it up, I used to pour a bit of foam at first and then a second pint poured immediately after was perfect. Then I started messing with things....
A few days ago I was fooling around with the placement of the temperature probe in my keezer and I put it up near the shanks thinking it would help to keep them cold. Well it did but it made the bottom of my keezer much too cold (some water I had in a keg froze) and I think this couple days where the temps were near freezing allowed more CO2 to dissolve into my beer and when I moved the temp probe back to the bottom of the keezer the beer was now over carbonated for the given psi/temp it is currently at. I think I'm going to try some of those de-gassing methods that people write about

 

[Kegtron]

OK, if things are getting that cold then over-carb is your most likely culprit. Check out the link on the de-gassing methods.

You can definitely solve this, but be patient - it takes a long time for temperatures to stabilize and dissolved CO2 to equalize, so make sure you wait several hours between adjustments.

 

[dsaavedra]

Ok I just tried the methods in the sticky thread for knocking carbonation out of an overcarbed keg by forcing CO2 through the beer with the headspace depressurized. Seems to have worked, my beers are now pouring smoothly with no excessive foam on the several small test pours I've done. I am tempted to call this case closed with over carbonation being the culprit. I'll see how things are pouring tomorrow after letting stuff settle for a day.

I also decided to tuck my 5 foot beer lines down into the keezer instead of coiling them on top of the kegs in an effort to keep the lines chilled a bit more (don't know why I didn't think to do this before). So far no bubbles in the lines and no bubbles squirting through the faucets.

 

[Kegtron]

Glad this worked out! The fast technique looks like a keeper...

Be sure to verify your keg temperature and pressure are balanced to make sure it doesn't slowly over-carb again.

 

[dsaavedra]

Glad this worked out! The fast technique looks like a keeper...

Be sure to verify your keg temperature and pressure are balanced to make sure it doesn't slowly over-carb again.

For sure. Since I've been kegging I've used the burst carbing method of hitting chilled beer with 35psi for 24 hours then purging the excess pressure and dropping to serving pressure of 11 psi for a day or two before pulling a pint. But after this episode I am starting to see the appeal of the pure set-it-and-forget-it method of just putting beer on serving pressure and waiting 7-10 days to dispense.

 

[Kegtron]

I'm a big fan of set & forget - less risky as you've discovered.

One way to speed up the set & forget approach is to push gas in through the beverage-out tube. This cuts the time roughly in half vs. the normal method as it bubbles up from the bottom and dissolves faster. If you do try this method, use a one-way check valve to ensure you don't get beer in your gas line.