So, I'm fairly new to homebrewing, about two years now. I started with bottling, then moved to corny kegs, which I'd just keep in the garage fridge, then put in a trash can full of ice and serve with a picnic tap. Now, finally, I got my first kegerator, and it's awesome. The first weekend I had it, anyway. The second weekend, I went out to get a beer. While it was cold and tasty, it was also flat. This has never happened to me before. Both kegs were flat, so whatever the fault is, it's not just the one keg. I set the CO2 pressure at 5psi above ATM, as I've found when using the picnic tap that keeping it above 10psi would give enormous head. Do I need to crank it up higher, at least during the week when I'm not drinking?
AWhy are you using a picnic tap if you have a kegerator? 5 psi is way too low. Your primary problem here is understanding the relationship between pressure, volumes of CO2 and applied pressure. Have you used a force carbonation chart in your home brewing? You essentially need to maintain the equilibrium that is created when you carbonate your beer. Assuming a middle of the road volume of CO2 of 2.6, and a temperature of 38F, your pressure needs to be around 12 psi to keep the carbonation in solution without over carbonating it. Also key is keeping a constant temperature from the keg to the faucet. If you are using a picnic tap and opening and closing the door you are setting yourself up for temperature swings that will make you unable to balance the system. Temperature changes will also cause foam.
I don't use the picnic taps anymore - that's why I got the kegerator. Sorry, I guess I was unclear. What I generally do when kegging is to fill the corny, and then put it under 30-35PSI at room temp for a week to carbonate. Previously, I couldn't refrigerate during this process because there wasn't room in my garage fridge for the corny AND the CO2 tank. When tapping, I would then bleed off the pressure to around 5PSI for serving. Now that I have a kegerator, I can carbonate while refrigerating the keg, so I don't think I'll need to go up to 35PSI. At least that's what I get from my reading. I'm new at this so I could be wrong. Anyway, if I grok your vibe correctly, I need to have my pressure set at around 12PSI to maintain carbonation while I'm not actively using the kegs. I typically only drink on the weekends, so they go unused Mon-Fri.
You don't adjust pressure to serve, you balance your system and leave it at that setting. My 12 psi is a rough shot at it. You need to get your arms around your temperature to really get an idea of where it has to be. If you have to adjust your pressure to serve you are not balanced and you need to address it. A lot of what you need to address depends on your system. What brand / model kegerator do you have, does it have a tower cooler, what type of faucets, how long are the beer lines?
Lemme see here...I only just got the thing a week ago. It's a Kegco MDK-209B-01. 3-tap tower, without a tower cooler. The taps are just the standard faucets, I guess. The beer lines are a couple feet long - long enough to run from the corny directly into the tower. I learned to adjust pressure back before I got the kegerator, when I was just using picnic taps. I'll just set it for 12PSI as a default from now on.
Without the tower cooler you are likely to suffer from first beer foam even if you are properly balanced. That is because the beer in the tower is warmer than the beer in the keg, your goal to prevent CO2 from coming out of solution is uniform temperature from the keg to the faucet. You likely have standard front closing faucets. You may find that without daily use they stick. Rear closing faucets will not stick, and are a nice upgrade you can add later. If while your system is at rest you see bubbles moving in the beer lines, then you are not balanced. Those bubbles indicate you will have foam when pouring. Looking at the lines is a good place to start.
I use picnics in my fridge because I'm too lazy to drill the wall. How long have the kegs been in? Unless you're one of the guys who try to carb for a few days at 30psi and turn down to 5psi to serve, you may need more time. I generally do the 12 psi and give it some time. And maybe down down to serve, since I"m also using picnics.
Nick - I just got the kegerator a week ago, so I'm still trying to figure out how it works. Up until then I was pressurizing at 30PSI, and storing the cornys in the garage fridge until serving. Then I'd stick them in a trash can full of ice and use picnic taps. Doug - OK, I'll check for bubbles in the line, too. 1. Up pressure to 12PSI, leave it there. 2. Check for gas bubbles in the line. 3. Be ready for head in the first pour, from warm beer in the tower lines. Good stuff, man. Thanks.
Oh, and I thought about drilling the wall to run a beer line, but as it's (A) a rental house, and (B) my landlord is Mormon, I figured it wouldn't go over real well. ;0
Also any adjustments you make will take time. Think stopping a train vs stopping a car. A good 12 hours for things to settle in. With the pressure, after 12 has sat for a while, pull a beer and check the lines. If you still have bubbles adjust the pressure up by half to one psi. Wait and repeat. Knowing the temperature of your beer will help get into the ballpark more quickly. All things being equal the higher the temperature the more pressure the beer will need to keep the CO2 in solution. To get the temperature, start with a room temp glass. Pull a beer, immediately discard or chug, pull a second one into the same glass. Take the temp with a calibrated thermometer without touching the glass. It must be in liquid, not foam. Also another little tidbit - pouring beer on foam causes more foam. If you see clear beer coming from the faucet, don't pour that onto foam or it too will be foam.
Will do, Doug. I'll also get a thermometer to keep inside the kegerator. I can bring home a unit from the lab with a record wheel so I can track the temp fluctuation over the week. I don't expect there to be much variance in a brand new machine, but it'll be good to have a baseline reading.
You want to get a handle on liquid temp, not air temp in the appliance. Air temp can be all over, but the mass of beer will hold fairly steady. However, the mass of beer in the beer line (tubing) is small and that will warm up quickly if there is not good air circulation. Warm liquid holds less dissolved gas than cold liquid = foam. We want to see constant temperature all the time. Use a reliable, calibrated thermometer. Even a few degrees difference will make a difference. We can jump to the point here. Get a tower cooler. It is not optional. Point 2. Your lines are too short. You are going to want about 6' of 3/16" bev line,if you have 3 feet forget it. Also, check out the other 3,000 posts about system balance that are on this board. Just read up man. Cheers.
