The ABC'S of Kegging Beer
OK, this is the correct way to deal with a new kegging setup...
First thing you always want to do is make sure that there is no pressure in the keg before opening it: using the pressure relief pin in the middle of the oval lid, bleed out all the pressure. You could conceivably kill yourself by opening a high-pressured sealed keg. Do not do it. When all the pressure is out of the keg, open the lid and make sure the inside is clean and shiny.
If you have a "used" Cornelius keg that has not yet been cleaned of sodapop, it is usually wise to unscrew the two metal "studs" ("in" and "out") which are threaded onto the top of the keg. If they are very tight, use a deep socket wrench (available from your local Home Depot): you will need either a six-point 7/8, a twelve point 7/8 or (less commonly) a six point 11/16. You can easily look at your keg and see which sizes you need. Inside the studs you will find a spring-loaded "pin/poppet" mechanism. This poppet can fall right out of the metal housing, so be careful you do not lose it down a drain.
OK, boil the studs, the poppets and the oval lid in a pot of boiling water for fifteen minutes. This will remove any potential soda smell...
After you have cleaned them, each of the studs that you removed NEEDS to be placed back on its proper side. Although the two studs may look similar, they are not cross-compatible. The gas stud needs to get threaded back on the gas side, and the product stud on the product side. They CAN accidentally be reversed very easily if you are not paying attention. The "gas" stud (the one for the CO2 connection) has grooved horizontal lines chocked into each of the corners around its base. This is to let you know that this stud is for gas only. This stud gets placed back on the "In" side of the keg. The product stud has no horizontal lines notched into its base. When reassembling, do not accidentally switch the studs and screw them back onto their opposite sides. Although the two studs look identical, they are not and later on the couplers you hook over them will jam on and not want to come off. BE CAREFUL!
Now the interior of the keg will need to be cleaned. Either use Tri-Sodium Phosphate or Straight-A (which I sell at the shop) OR use plenty of boiling water. Fill the keg and let it sit for thirty minutes. Then empty and rinse. This should remove all organic matter and residual cleaning chemicals from the keg. Visually check the interior and smell it. If it needs more cleaning, do it again. Check to make sure no bits of organic matter are on the tops of the interior tubes (both the long and the short one), stuck underneath the rubber O-rings. (The tubes can both slide out, once the metal studs have been unscrewed from the top of the keg it's always good to check under the flaired tops of the tubes....)
OK, now screw the studs (with their spring-loaded poppet mechanisms inside) back onto the keg IN THEIR PROPER PLACE. The keg is now cleaned. Sterilization should take place just before you fill it with beer.
To sterilize a keg, the only substance I recommend is BTF Iodophor. Chlorine will react with stainless steel and corrode it Do not use bleach. Iodophor should be mixed in the keg at the EXACT ratio of one tablespoon per five gallons of cold tap water. Seal the lid. Shake and roll around a few times and leave the Iodophor in the keg for at least four or five minutes, then open and dump out the solution. The keg is now sterilized and the residual BTF in the keg does not need to be rinsed out if you don't want. At the concentration used it will not affect flavor, aroma or yeast performance. If you feel uncomfortable with this fact, rinse out the keg with a dash of cold water. The keg is now sterilized.
Usually we tell people to rack the beer out of their primary fermenter when the airlock is bubbling once every ninety seconds. If you are using a Cornelius keg, you no longer have to transfer to a secondary glass carboy - your keg can be your secondary. If you are going to do this, and not age the beer in a glass secondary, I recommend that you wait an extra day or two past the "one bubble every ninety seconds" rule. Your primary activity will be almost non-existent (one bubble every two to three minutes), and your beer will be a little more settled out and ready to go into your keg.
Siphon your beer carefully into the keg either after primary or after secondary aging in a glass secondary. Put on the lid and now you are ready to hook up your CO2 bottle and regulator.
Some regulators need a hard fiber (or plastic) washer between them and the CO2 bottles, and some have an internal black O-ring. Be sure your regulator has one of the appropriate washers/rings in the hex cup before you seal it onto the CO2 bottle. Hand-tighten the regulator onto the CO2 bottle, and then - using a good long crescent (or adjustable) wrench, with lots of torque, finish tightening the regulator SECURELY onto the CO2 bottle. Compressed gases will find any leaks, trust me. (Do not use a pipe wrench - it will bite into and nick the brass of the regulator.) Be sure the gauges have not rotated themselves upside down when you are done tightening the regulator will be locked into position and you will not be able to adjust the position of the gauges, so be sure they are upright and visible when the regulator is fully tightened.
Now, push your red airline all the way onto the barb on the regulator. Lock it down TIGHTLY with the provided hose clamp. Open up the "main" on top of the CO2 bottle. On your regulator, screw the center screw INWARDS (clockwise) to turn the pressure up to 30 psi. Now, using soapy water check for leaks AT ALL CONNECTIONS, and if necessary, tighten everything down again until no leaking bubbles can be seen. Leaks can - and usually will - be found at the following connections: where the regulator nut screws onto the CO2 bottle, where the red airline clamps onto the regulator barb, AND at the end of the red airline, where the check valve and grey coupler are located. Submerge that whole end piece (check valve/coupler assembly) into a jar full of water and look for bubbles coming out along its length. Tighten down all leaking connections, especially where the regulator hooks onto the CO2 bottle!!
Once you are sure you have no leaks, you are now ready to pressurize your keg full of beer. Be sure your regulator gauge is reading 30 psi, your "main" is open, and your toggle switch on the regulator is pointing downwards.
In all circumstances, do not carbonate your beer - or pressurize your keg above 10 psi - with your product line/faucet assembly attached. Keep your product line *disconnected* until you are ready to serve your beer, and the keg pressure has dropped to 10 psi. If you need to increase the pressure later on, be sure to remove your product line. Reattach it after you have dropped the keg pressure back down to 10 psi or less.
Hook your grey CO2 coupler onto your keg and put in 30 pounds of pressure. Turn the toggle switch on your regulator sideways (off) and bleed all the gas out of the keg through the lid's pressure release. Open up the toggle and refill the keg with another 30 psi, then toggle off and bleed it out again. Do this three times total, and then put in ANOTHER 30 pounds (for the fourth time). If the lid does not seem to be sealing very well, one of two things is happening. Either you are not putting in enough pressure to "push" the lid up against the top to seat it securely against the inside of the keg, or the lid is not in its little "nook" and needs to be realigned. In either case, make doubly sure the lid is not leaking. Re-position it if you detect a leak until it seats properly.
The "three-times 30 psi" purging you've just done is extremely (VERY) important - you are purging the oxygen out of your keg, and if you do not do this, you will oxidize AND RUIN your beer in a day or two. Now, that you have purged your oxygen, you have a few options.
Option One: You can now disconnect your airline, leaving the 30 psi in the keg, and leave your keg at room temperature for a week or two (or more). This is usually a good idea if your beer was racked in directly from the primary fermenter, or if you are dry-hopping, or if you are lagering the beer (in the keg) in a cold environment. The beer will be safe and sound for months and months left in there. (Assuming you've left 30 psi in the headspace, you have no leaks and your temperatures are not extraordinarily high.) Your beer will NOT carbonate under these conditions, and eventually you will have to do one of the steps below.
Option Two: You can also take your newly-filled keg, and stick it directly in the refrigerator. If you do this, be sure you have no residual fermentation still going on, or it will "crash" the fermentation and you will be left with sweet beer. Leave your airline on, 30 psi on the regulator, gates open, and let the CO2 infuse into the keg over a period of two days. This will carbonate the beer. After about 48 hours, (depending on temperature of the refrigerator, personal preferences, etc.) the beer will be ready to tap. You can now serve the beer OR you can pull the carbonated keg of beer out of the fridge, stick it in a corner of your house and let it sit for weeks or months until you are ready to serve it. Always leave 30 psi in the headspace (to keep the keg sealed off), but do NOT leave your airline and regulator hooked onto it. Whenever you want to serve it, throw the beer back into the fridge (or an icebath) to chill it down, and your keg will be ready to drink in a few hours.
One of the golden rules of kegging is NEVER store beer in a keg that is not pressurized with CO2. Gravity will be pulling the lid and the gaskets down, thus allowing oxygen and bacteria in. At 20 to 30 psi, the lids are pushed up from within, sealing everything tightly and making your keg inaccessible to the outside world....
CONTRARY TO WHAT ANYBODY ELSE TELLS YOU: DO NOT SHAKE YOUR KEG. THIS IS UNNECESSARY AND ONLY RESULTS IN "GREEN"-TASTING, CARBONATED BEER. As previously described, to carbonate your beer: let the keg sit for two days: gas-line and regulator on, connected, and feeding in at 30 psi. Then, after 48 or so hours, lower the regulator pressure to 8 - 12 psi, bleed the 30 pounds out of your keg, and allow the 8 - 12 psi to enter. Hook up your tap line and sample the beer. If you like more carbonation than what it has, increase pressure back up to 30 psi for another 4 -12 hours. Repeat to sample the next day.
If you beer has too much carbonation (i.e., is too "fizzy"), take the keg out of the refrigerator and turn off the CO2 supply to it. Bleed out all the pressure. Leaving it unrefrigerated, bleed out the pressure every few hours for one day. Then put it back in the refrigerator, chill it down and dispense using 8 - 12 psi. This is usually not the problem, however, after only two days under pressure. You will get a feel for your exact carbonating times after a few tries...
To naturally carbonate, although I do NOT recommend it due to the troubles of keeping your keg warm enough to achieve proper yeast fermentation (at least here in the Northwest), do the following: CONTRARY TO WHATEVER BOOK YOU HAVE READ, you need the same amount of sugar (or malt) to carbonate five gallons in a keg as you do five gallons in bottles. (Unless you are going for flatter "cask-conditioned beers - then you can use a half cup of corn sugar...) After siphoning your beer into the keg, add 3/4 to one cup of sugar, boiled with a pint of water. Lock down the lid and add 30 psi to the keg 3 times, bleeding it out after each time, then add 30 psi a fourth time and disconnect your airline. This is a necessary step in order to seal the lid and the O-rings up against the metal. Without this, all your carbonation will leak out through loose holes in your seals. Put the keg in the warmest room you have - I used to leave mine on top of floor heaters and still not get proper carbonation. Dispense as normal in three to four weeks.
OK: here are the FAQ's I get about kegging.
CARBONATING AND SERVING WARM AND COLD: In order to carbonate beer using the above method, the beer needs to be cold. As a law of physics, cold liquids absorb gas, warm liquids reject gas. You can test this at home by opening a Pepsi that's been in your car on a hot day - it foams like crazy as it tries to release the gas it is holding within it. What this means for you is that: cold beer will absorb gas and carbonate nicely, warm beer will not. Also: beer that is being served warm NEEDS less carbonation in order to feel "right." This is the basis of "cask-conditioned" beers they are served warmer and "flatter." Cold beer needs to be highly effervescent in order for the carbonation to be evident to the tongue.
In a nutshell, carbonate and drink your beers within the same temp range. Do not attempt to force-carbonate them warm, and then chill them down for friends - you will be serving flat beer, and vice versa, do not force-carbonate them cold, and then serve them warm at a picnic - you will be serving foam. Temperature affects gas solubility in liquids, so stay temperature-consistent unless you really know what you are doing.
THE HIGH PRESSURE REGULATOR GAUGE: Most of the kegging systems I sell come with a double-gauge regulator. The second gauge, on the left, is the high pressure gauge - it is reading the pressure inside your bottle of CO2. What you have in your bottle of CO2 is liquid carbon dioxide - it is boiling off to carbon dioxide gas at 850 psi (room temp) and you are sucking that gaseous vapor out the top to use for your keg system. (The fact that you have liquid in there is why you can never lay your bottle of CO2 on its side and use it - the liquefied gas goes into your regulator which makes it act weird.)
As you use up your liquid CO2, you have no dipstick that is running down through the liquid telling you how much you have left. Therefore, whether you have a full tank of liquid CO2, or one drop left, you will be reading 850 psi ( at room temp). Once that last drop boils off to vapor, and you have nothing to replace it with, then you will start to see the needle drop rapidly through the red zone until you are empty. Usually this takes a few days. It gives you fair warning NOT to throw a party in a few days as you are dropping low. IT IS NOT, AS I HAVE SAID, GOING TO TELL YOU YOUR TANK IS ONE-QUARTER EMPTY, HALF-FULL, ETC. Treat it like a "fuel light" not a fuel gauge.
And on a final note, putting the bottle of gas in the fridge will cause the reading on the gauge to drop to 500 psi. This is not a loss of gas, it is just a lowering of temperature - it will come back up when you warm up the bottle. Temperature and pressure are connected (as Boyles and/or Charles figured out in the 19th Century) so do not worry it does not affect your keg set-up to have your C02 bottle in the refrigerator.
Enjoy your keg setup! It is the most enjoyable thing you can add to your homebrew setup!