I've had the same setup for about the past year and half, and have been really happy with it. Its a small under counter fridge with two cornies, 2m 5/16 lines, each going into celli taps which are mounted on the door. Its a pretty simple setup and have had great pours from it. Lately for some reason though, I'm getting persistent foaming in the lines, and I can't for the life of me figure it out.
It's happening on both taps, I've tried changing the seals on the dip tube/posts, trimming the ends of the lines where they meet the taps, rinsing the lines with a strong PBW solution, raising them above the kegs rather than having them just hanging down, turning the temperature down (from 6c to 4c), dropping the serving psi from my usual 20psi to about 10psi ... just nothing seems to help.
It seems that very soon after the beer leaves the keg CO2 is coming out of solution as loads of little bubbles, as soon as it hits the faucet they just strain through the flow control and come out as pure foam.
Really at my wits end here, have wasted a good few litres of beer by now trying to troubleshoot this. If anyone had any other ideas what might be happening would really appreciate.
Have you put any 90s or new connections on recently.
Strip the corny post and give a good clean
Keg lube or Vaseline on rubber post rings
Some good tips here - http://www.kegman.net/foamy-beer/#Wild might be something that you have not tried. I would advise going through each of them.
Shanna
Have you taken the tap off to make sure it isn't clogged with hops?