I can't help but notice the tremendous number of people complaining of foam in the kegerator setups. Having taught myself how to get rid of this problem, I'd like to share a few tips with you all. Lets start with the keg and work out way to the glass as a logical progression.
Beer: Fresh, cold, and settled. Fresh means fresh. If your beer is a few months old, it is exponentially more likely to have foam issues from secondary fermentation among other things. Cold is below 40 degrees. I see 42 degrees listed as the maximum temperature for holding beer. I'd like to protest that number from a serving standpoint. 42 degree beer means a box temperature of around 41-42 degrees. This isn't going to help pour a decent beer because it is going to require a regulator setting so high your line resistance balance point is going to be so high you'll need a ton of line and your still asking for it. Stick with a product temperature of 36-38 degrees. To achieve this, I havea box temperature of about 34-35 degrees ambient when the thermostat becomes satisfied and shuts off. This temperature is going to be important later, but wait for that. Settled just means that the keg has had time to chill in the kegerator. Where I get my kegs (I admit, I don't brew beer, but that doesn't make me a bad person) they are generally about 40-44 degrees, and by the time I bounce them all the way home in Arizona I am lucky if they are still under 48 degrees. So they need to chill and settle (temperature drop + (re)absorbition of CO2. Side note here, make sure your regulator to tap setup has been purged of oxygen before you tap the keg. Otherwise you are putting a big slug of air into your keg.
Ok so thats covers the beer. Now the tap setup, which in my book is the regulator, gas line, and tap, but no further. Two words this time. Clean and working. Seems simple, but I have taken apart so many taps full of goo it makes me ill. Taps do come apart. Doesn't take a motorhead to figure this out. clean them, scrub them, sanitize them, lubricate the O-Rings, replace worn/broken parts, etc. Working. Worn parts again, and cheap chinese regulators. There are so many different types and brands of regulators it would be impossible to cover them all. Nor do I advocate taking your regulator apart. But a welding supply shop could do this for you. If your regulator routinely creeps way past your original set point, its time for a new diaphram and spring. If its cheap, don't bother, get a new one. I like Smith, but there are others and I'm not a product endorser so do your own homework. Even good regulators creep a little from time to time. Use a BALL VALVE ON YOUR GAS LINE. TURN IT OFF WHEN YOU ARE NOT DRAWING BEER (but leave it on for an hour after a lot of beers have been drawn, or while a new keg is cooling). The spill you limit to a puddle instead of a collapsed celing might just be your own. I am a HUGE advocate for STAINLESS STEEL taps and faucets. Lets talk about that more later though.
Beer line. Micro-Matic or similar. If you are using that cheap thin wall vinyl tubing that came with your kegerator still, shame on you. For kegerators, 3/16" beer line or don't bother. Many retailers of keg beer have this line sitting around the shop in one form or another. I like the clear Micro-Matic line, but the Perlick black line used to re-hose pumps is really really nice too (but you can't see inside, so cleaning requires faith, something I don't have).
Beer line routing. Up, Up, and Away. No I'm not talking about superman or your drivers education teacher, but its simple. Create a trap in your beer line and you are going to have brix stratification. Thats the seperation of the dissolved CO2 gas from the beer in the lines. Little pockets of gas that sit in your beer line waiting for you to pull the handle so they can rock your faucet and lines with a hydrostatic shock and fill your glass with foam. So keep beer lines going up from the keg. That is so so much easier said then done. But there is help - Use a Perlick Lo-Boy tap. It dumps beer out just slightly above the Sankey, and from the side instead of straight up. Try coiling your beer line from the Lo-boy around the edge of the keg (another use for Duct-Tape!) and then up. This Up Up and Away thing usually isn't such a big problem with 1/4 kegs, because there is generally a lot of space between the top of the keg and the faucet, but with 1/2 barrels, well you all know what I am talking about.
Beer Tower - The MOST IMPORTANT PART ABOUT IT. This MUST be refrigerated. Insulation is NOT refrigeration. I have seen many attempts, but the thermometer is king here. Working in refrigeration, I have tons of thermocouple type measuing devices, and my kegerators have looked a lot like NASA experiments at times. All this work has lead me to believe there is no substitute for what I can Co-Axial Forced Air cooling, or a Refrigerated Glycol Loop. Lets start with the Co-Axial Forced Air cooling because it is the cheapest, and in many ways the most effective. Puting a fan at the bottom of the tower is not a good idea. It may keep the beer line cool, but at what cost to: 1. The box temperature 2. The little undersized compressor dealing with the loss out the top (the only way to get enough flow to actually keep the line at keg temperature) and 3. your electric bill. But the fan wasn't a bad idea, it just needed improvment. If you have a forced air cooled box (like a silver king, true, bev-air, etc) you are in luck. If not, you will need a small (>3" computer cooling fan to force the air. The next thing is a piece of flexible 1" I.D. braided vinyl or PVC tubing. You will need one of three PVC couplers, either a 180, 90, or 45 degree elbow. Depending on what kind of fan you have you may need something more to attach the fan. If you have a forced air box, then the angle couplers with a couple holes drilled in them so you can zip-tie them to the outlet air grate of the evaporator section (hence the angles, the tubing isn't very flexible, and you may need the angled couplers to get it to work. Then a hole big enough to get your beer line through (drill it, please) set back at least an inch longer then your tower height. Basically you are going to use the fan, or the fan you add, to suck air directly from the evaporator section of the kegerator and force it up the draft tower with the beer line inside. That air temperature for me when the unit is running is typically 28 degrees, and never more then 36 degrees when the compressor isn't running. This keeps the beer keg temperature. And it allows that same air to return to the box by being forced back down the draft column because it is capped and sealed off. You will need to insulate the draft column, and your not going to have a ton of room, so a sheet of cork insulation cut to size and rolled up works nice. Otherwise you are going to have a ton of condensation on the outside of the column, causing damage to whatever it drips on. With this system, at rest the temperature of the faucet is still below 42 degrees, and will remain under 40 during service as long as a beer is pulled <30 minutes. Parts express sells the fan you want, partsexpress.com 259-115, and get a transformer from around the house or try ebay for a "200ma adapter" and get something that does 9v-12v.
Faucets and more on Stainless steel and Hygiene. I hate foam, and I hate cleaning. If you keep your lines and faucet cold like I do, you really don't have to clean. Use stainless steel shanks, faucets, and tap if possible. I haven't found a Lo-Boy style tap made out of stainless steel, but please let me know if you have. Using chrome plated brass taps is a bad idea. In a bar, doing volume, its not likely that any one person consumes that much metal, but at home where a unit may sit for a day (or more, shame on you) the CO2 in suspension (now carbonic acid) and natural acidity of the beer eat away at the chrome and brass. Chrome plating is a nasty business, and if you think they keep there plating materials free from heavy metals because it is a food service item you are sadly mistaken. Chromium by itself is not nice, but its electronegatively similar friend Cadmium really isn't very nice. Neither is the lead found in brass from recycled plumbing parts among other sources, nor is the copper used in making brass. Try and use all stainless steel parts. Lubricate probes and mating surfaces to slow down the scratching and grinding that just accelerates this if you have brass and chrome products. Vent-Matic is the WAY to go for sure on the faucet. Up to the sealing area, my tap is below 40 degrees all the time. I don't have to clean it once a week, and neither will you if you follow these tips. only the screw-off nozzle gets cleaned around here, and that takes about 30 seconds.
Ok enough for tonight.
cheers
I think it's true though, you need to get experience with your own setup. Most of the foam issues probably come up with beginners just setting up their draft systems.
