New Micromatic kegerator foam/flat beer issue

[killedwithcash]

So about two or three weeks ago I setup a Micromatic kegerator in an old fridge that we have. I bought a corny keg to put my most recent beer in which was a Saison. I wanted my carbonation to be pretty high because of the style so I set the CO2 at 18 psi, shook it a few times and then left it for about a week. I think my temperature is around 40F, but when I went back to try the beer. I lowered the pressure to about 10 psi and the beer came out all foam and seemed flat. I also noticed that there was foam in the lines. I then put it back up to 18 psi and tried it there and it still would not pour correctly. I have 5 foot lines and one thing I did forget to do was sanitize the lines before hooking it all up. Could this be a problem? Or something else?

Sorry, if this has been posted many times before. I have looked through all of the previous articles and cannot find a solution.

 

[LLBeanJ]

Sounds overcarbonated to me. 18 PSI @ 40°F is going to put you at about 3.0 vols, which will be very difficult to manage with a 5' draft line. The general rule of thumb is 1' of 3/16" beer line for each PSI you plan to carb/serve at, so you would need about 18', give or take, to make this work. Alternately, a flow control faucet (e.g. Perlick 650SS) could get you there, but you may still have foaming troubles. I'd start with either lengthening the line or reducing the level of carb. To get a good pour with a 5' line will require dropping the carb level down to about 2.0 vols.