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I recently bought an Igloo 6 ft^3 kegerator as my first venture into kegging. It worked very well the first day but has been pouring wildly ever since.

  • The beer line is 4.5 feet of 3/16" PVC; based on the numbers from Beersmith, this is a good length to get 1 PSI at the tap for a keg pressure of 12 PSI.

  • I left a pint glass of water overnight in the bottom of the kegerator; it measured 32° F this morning. I'm doing another glass on top of the keg tonight but I can't imagine it'll be anywhere near 40° F.

  • I plan to pick up some ½" copper tubing to insulate the beer line in the tower and install it when the parts for my Sanke to Cornelius kit comes in, but because I'm still getting extremely foamy pours two and three pours from the first, I don't think heat is the major cause of these problems.

This brings me to the regulator, which I think might be faulty. A couple observations and questions:

  1. Is there supposed to be any difference in the reading between the pressure with the shutoff valve turned "off" and "on"? With the valve off, I set the regulator to 14 PSI; after turning the valve on, the pressure drops to 9 PSI and stays there. 18 drops to 10, 20 drops to 14 (and then creeps slightly downward). Is this normal? Is it safe to employ a little Kentucky windage on this system? Is it okay to open the shutoff valve and then fine tune the regulator?
  2. What is a "normal" magnitude and velocity for needle creep? I'll find that I thought I set the pressure to a stable 12 PSI but when I open the door 15 minutes later it's at 13-14 PSI. When it does this, do I just tweak the regulator and go on about my day? (And how will that affect force carbonating my home-brews?)
  • What does wild mean? And is it consistent? – Pepi Jan 6 '15 at 4:02
  • By "wild" I mean that each pour is 50-80% foam. Consistent in what way? – Grafton C. Jan 6 '15 at 14:09
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'because I'm still getting extremely foamy pours two and three pours from the first, I don't think heat is the major cause of these problems.' I think you're right.

If your fridge really is 32 deg. the foaming might be an issue of over-carbonation. Fully saturated, beer at 32 deg/12 PSI will be carbonated to 2.9 volumes (if you're dispensing with pure CO2, which I'm sure you are). Bump this up to 14 PSI for long enough and the carbonation would eventually get over 3.1 vol. At 40 deg. you'd still be at 2.47 and 2.65 vol., respectively, which is not at all inappropriate for some styles, but getting towards the high end if you ask me.

'Is there supposed to be any difference in the reading between the pressure with the shutoff valve turned "off" and "on"' Only if the system has lost pressure somehow, and you'd hear a hissing of gas and see the needle going back up to where it started as it re-pressurizes. Sounds like your regulator is faulty, as you suggest. Try tapping the gauge, or quickly popping the pressure relief valve open a few times to see if this resets the needle. Fine-tuning it with the valve open might work (see below), but there's probably no reason to think the gauge will read more accurately that way.

It might be best to adjust the regulator pressure based on the flow rate at the tap. Since it's the only variable that's really easily controlled (much more so than accurately changing the temp. of the fridge or the resistance of your beer lines [but also see below on that]), I think adjusting that, even by eye, makes the most sense. See how low you go can while still getting flow, and see if that helps your foaming. This will at first just be due to lower velocity out of the tap but the lower dispense pressure will eventually lead to lower beer carbonation as the liquid and head-space gas pressures equalize (this can take days, especially at cold temps), so you may have to do fiddle up and down to balance flow and carbonation.

As I mentioned before, the setup you have may also just be improperly balanced. Balance in draught terms means applying the right pressure on the keg to overcome the resistance of the system, while maintaining the right carbonation level in the beer. According to the Brewers Association Draught Beer Quality Manual, your tubing alone (PVC, 4.5 ft. @ 3/16th") should give you ~13.5 lb. of resistance, not accounting for other resistance such as from the faucet, or the height of the faucet above the keg. This means you might actually need to apply almost 15PSI to the keg to achieve proper dispense velocity. You may in fact be doing this, if you don't really know what your pressure is set to. 32 deg/15 psi will give you carbonation at almost soft-drink levels (3.2+ vol), and 40 deg/15 psi is still high at almost 2.8 vol. If this is in fact the issue, you'd just have to cut the line down a bit and reattach it to the shank inside the tower, giving you less resistance (shorter line = less resistance) and therefore lessening the pressure you need to apply to the keg, allowing you to maintain a proper carbonation level.

It's always helpful to remember that the carbonation level of a beer is really a matter of only two factors: temperature and pressure. Increasing pressure and decreasing temperature both have the same effect of increasing carbonation, an important factor when trying to get a draught system working just right.

Bonus: Here's a good chart that illustrates the relationship between temperature and pressure in beer (and is indispensable to me): http://www.zahmnagel.com/LinkClick.aspx?fileticket=HuVGZ8tLaow%3D&tabid=81

Hope that helps.

  • This is fantastic, thanks. The issues I was having with the regulator were solved by venting the keg and re-pressurizing at a lower PSI. I've replaced the 4.5' line with a 10' 3/16" PVC line for more flexibility in troubleshooting the balance. Unfortunately, all the research required to ask my question in the first place ended up kicking the keg I had, so I'll have to get back later with the results. – Grafton C. Jan 7 '15 at 19:10
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    No problem. However for balancing the system, you'd want a shorter beer line, rather than longer. This post does a good job explaining the process of balancing. Really you want to start with choosing your desired carbonation level, working backwards to figure out what PSI you need on the keg to maintain that (based on the fridge temp), and then figuring out the line length needed. – Franklin P Combs Jan 7 '15 at 23:37
  • I reduced it to five feet, but I do have a question about balancing. Is it a one-time calibration with a known CO2 vol, and then every subsequent keg is run at 10-12 PSI (after carbonating whichever keg is about to be tapped)? – Grafton C. Jan 8 '15 at 3:45
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    Pretty much. You can still run kegs at different pressures, for sure, but they won't pour as well since the setup wouldn't be optimized for that serving pressure. I'd pick a range of carbonation levels (~2.3-2.5 volumes is what I like for most beers) and balance the kegerator to be right in the middle of that range. That way you can go up or down a couple PSI and still be fine. – Franklin P Combs Jan 8 '15 at 4:10

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