4 tap keeper - 1 tap has foamy first pour

[OscarBrau]

I've been trying to figure out an issue with one of my kegs, and just haven't been able to solve it. I have a four tap keezer - all of the tap lines are the same length, and carry approximately the same serving pressure. There is a fan running to keep the air circulating. Three of the taps are fine - perfect pours every time, even if they've been sitting for a week. One tap, on the other hand, spits out a lot of foam for the first pour, before settling for subsequent pours. It's happened across two beers now. I've thought of the following issues:

1) too low of pressure, causing beer to go back into the keg and creating air in the line. This seems possible, and on the prior keg I upped the pressure and it seemed like it helped the issue a little. On the current keg it doesn't seem to have helped.
2) Co2 is coming out of the beer and creating pockets in the line. This seems possible, but seems like it should be happening on the other lines too, but isn't.
3) Bad liquid post causing issues. Haven't tested this and I don't know if that's even a realistic concern.

Has anyone else experienced anything like this? Any tips or suggestions? Thank you!

 

[day_trippr]

- Have you tried swapping one of the "good" lines with the "bad" to prove the problem is the keg?
- CO2 break-out can happen if the keg was carbed to a level higher than the dispensing temperature and CO2 pressure combination can support.
- If these are cornelius style kegs the small O-ring under the Out dip tube flange is critical to keeping CO2 in the head space from being injected into the beer stream. Worth inspecting...

Cheers!

 

[OscarBrau]

Thanks for the reply, day_trippr! After your response, I tried swapping the lines. Nothing changed. Then, I swapped liquid posts with one of the other kegs. Nothing changed. I swapped out the dip tube o-ring, even though it seemed okay - nothing changed. Seems like it might be a carbonation issue at this point? The first pour is because there's a bunch of air in the line - I can see it clearly.

 

[day_trippr]

Thanks for the reply, day_trippr! After your response, I tried swapping the lines. Nothing changed. Then, I swapped liquid posts with one of the other kegs. Nothing changed. I swapped out the dip tube o-ring, even though it seemed okay - nothing changed. Seems like it might be a carbonation issue at this point? The first pour is because there's a bunch of air in the line - I can see it clearly.

Certainly overcarbonation - or too low a dispensing pressure given a properly carbonated keg - can cause the exact symptom you are seeing. You have to decide which cause is in play...

Cheers!

 

[OscarBrau]

Thanks for the info! I purged the keg and shook it to release some of the gas before resetting it. Seemed better this morning. I wonder if part of the problem is that I naturally carb with dextrose rather than force carb, so I risk the serving and keg pressure not being in close alignment? Something for me to think about going forward.