Slow Draft System When Filling Growlers

[WitsEnd]

Our taproom has been booming! We started selling pints and growlers through our taproom the second week of January.

On a Friday night from 4-7pm, we burn through 8-12 1/6 bbl kegs and often are filling up to 4 growlers at a time.
We've noticed that when we're filling many growlers consecutively, the system slows down quite a bit.

During slow times, we're pouring about 2 oz per second, as recommended by the Draft Quality Manual. During busy times, that can double.

This was my original gas setup:
Tank Regulator (with check valve) set at 25 PSI
about 20 ft of 3/16" ID line to a secondary regulator (with check valve) set at 11 PSI
3 ft of 3/16" ID line to 4-way manifold (no check valves).
2 ft 5/16" ID line to a keg coupler.

I just replaced all the 3/16" line with 5/16", so everything is now 5/16"
I also increased the tank regulator to 40 PSI
This Friday seemed to improve it slightly, but we still saw a slow-down when filling multiple growlers.

I'm assuming it's my gas system that can't keep up with the emptying kegs, but I thought for certain the larger feed line and higher pressure would take care of it.
I'm more concerned as I will be adding another 4 lines next week and another four in the future.

Has anyone had any experience with this and what would you suggest?

Thanks,
Patrick Sundberg
Jack Pine Brewery
Baxter, MN

[panadero]

We have eight serving tanks, and up to eight kegs at any given time. I have 3/8 id line all the way to the kegs and tanks. Two secondaries in the tank cooler, and two in the keg cooler.I have a dual primary reg - both set to 30psi. One of these lines goes to the tanks and is split at the secondary set at 11 psi. The other goes to the keg dual secondary, also at 11 psi. The keg lines are the ones that tend to slow down - due to less head space I assume - but never enough to cause a bad pour. We are filling at most two growlers at a time, though, so less draw to the system. I was going to try two tanks of co2, but the dual regulators splitting the draw really improved it enough for us.
Hope this helps.
David

[Matt Dog]

Best practice would be to have individual regulators for each keg, otherwise one cant keep up w multiple kegs. You could also crank the keg regulator up a few psi during those high volume times, as long as you set it back at the end of the night so as to avoid overcarbonating the remaining beer.

[gitchegumee]

I think you need more regulators (or a larger regulator). Cranking up the pressure is NOT the way to solve this. It will tend to overcarbonate if left at a higher setting than saturated at your desired carbonation level. A larger regulator offers more FLOW at a given pressure. The decrease in pressure you are seeing when tapping multiple kegs with a single regulator is referred to as "droop" in regulator parlance. It means you are asking more flow than your regulator can handle. It sacrifices pressure to try to keep up with flow. Since most CO2 regulators are made for a single draw, I would follow Matt Dog's advice and add independent regulators to each keg.

[WitsEnd]

Problem Solved!

I switched to a separate regulator for each keg and that solved it.
No more slow pours and regulator droop when we get busy.

We went to multiple tap lines for our main beers, so in an effort to gain more room in the cold room, I have a draft line splitter at the keg coupler. I now notice that if we fill two growlers off that line, we are seeing it slow down. It's not as bad as it was before, but it is noticeable.

I may look into getting a higher-flow regulator, or perhaps try to tie two regulators to those kegs. The second isn't ideal, I'm sure, but I have the regulators already set up, so I doubt it'll hurt.

Thanks for the help!