Gas Line Length?? Does it Matter?

Post by **BlackDuck** » Tue Apr 12, 2016 11:08 am

I know that the beer line length can definitely have an effect on the carbonation level of the beer in the glass, but does the length of the CO2 gas line have an effect?

Here's a little background. When I bought my system, I bought a dual regulator and it was built with 3 foot of gas line for each side of the regulator. I recently added a "wye" adapter so I could run a total of 3 kegs. However, when I made this addition, I purchased a 4 foot gas line figuring that I would use this line on the keg that was furthest from the CO2 tank. I recently kegged my Kiwi Express IPA. I let it sit for 7 days at 12 psi, which is my normal time and pressure, before tapping. 12 psi for 7 days has always given me a great pour. Keep in mind that I'm using the 4 foot gas line on this one. On this case, after the 7 days, it was just barely carbed. Very little head and had a somewhat flat carb level to it. I checked for leaks and could find none. I did the first pour on Sunday, after noticing the lack of carbonation, I increased the pressure to 14 psi. I tested again last night, 24 hours after it was increased. It is improving as there was a little more carbonation, but not yet where it should be.

So, could the extra foot of gas line have this effect?

BigPapaG · Post by **BigPapaG** » Tue Apr 12, 2016 11:33 am

Chris,

Gas line length should not matter... But here is what might...

Are you using one way valves after the regulator or y-adapter?

If not, all three of your kegs will attempt to equalize.

This could cause issues when trying to force carb one keg while two others are already carbed...

At serving pressure, that third keg will take a long time to carbonate, just as it would if it was the only keg on the regulator...

Turn up the output pressure and now all three kegs have more so while you are force carbing the third one, you are also adding pressure to the two previously carbed kegs causing them to over carb.

I have a one way valve on each of my outputs as well as a shutoff valve so I can isolate each gas line at a specific pressure...

In your example, I would shut off the valves at the lines that feed my previously carbed kegs while set to serving pressure.

Then open the line to the keg I want to force carb... And raise the regulator pressure to say... 20-25 p.s.i.

Then close the valve to keg 3 (trapping 20-25 p.s.i in the keg)...

I then lower the regulator back to serving pressure and open all three shut off valves.

Since I have the in-line one-way valves on each line after the splitter, they only allow gas to flow to the kegs, not back to the y-adapter... So, each keg stays at it's pre-defined pressure!

I repeat the pressurization of keg 3 in this example a couple of times over a four to six day period as gas is absorbed into the beer and then, when I feel it should be ready I release the pressure and set it to serving pressure as well and voilá... Good to go.

This is a pic if the units I use... It is a combination shutoff and one-way... I have one on each gas line after the splitter but before the keg feed line. As such, I can play with pressures using a single regulator.

Just remember when lowering pressure to release the pressure in the keg you are lowering, then reattach the gas line and set pressure (else the regulator dual will be reading the high pressure between the regulator and the one-ways)... Not a problem when increasing pressure as the dial reads what it is outputting... But one the line has that high pressure, it will stay there until one of the outputs is lowered, dropping the pressure in the little section between the dial and the one-ways to a lower value for the line you are adjusting.

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Inkleg · Post by **Inkleg** » Tue Apr 12, 2016 11:38 am

No, psi is psi at 1ft or 100ft. Volume would be different if the inner tube diameter is, but I assume it's the same gas line. Is your tank getting low? the gauge will show pressure till the end. You would have to weigh it.

Post by **BlackDuck** » Tue Apr 12, 2016 11:45 am

Papa....great information. After reading your reply I realized that I left out some pertinent information.

Even though I can run 3 kegs now, I only have two hooked up. One to each regulator. These are the valves I'm using between the regulator and the gas line. And this is the regulator that I'm using. The keg that is already carbed is set at 10 psi (for some reason, 12 was just a little too much for this recipe). The new one is hooked up to the other regulator and is now set at 14 psi. You mention that all the kegs would attempt to equalize. But how can that be if I'm using a dual regulator?? If that's the case, what would be the purpose of having a dual regulator with the ability to adjust each on to it's own pressure.

Post by **BlackDuck** » Tue Apr 12, 2016 11:46 am

Inkleg wrote:Is your tank getting low? the gauge will show pressure till the end. You would have to weigh it.

This could be a possibility also.

Dawg LB Steve · Post by **Dawg LB Steve** » Tue Apr 12, 2016 11:55 am

What Papa said about them equalizing, that was the problem I was having when I was bottling with picnic tap. I would pull the keg I wanted out, turned down the regulator, purged the keg I was going to bottle from, took a bit to figure out the other two kegs were backfeeding higher pressure into the keg I thought was set to 4 lbs.

BigPapaG · Post by **BigPapaG** » Tue Apr 12, 2016 12:16 pm

BlackDuck wrote:Papa....great information. After reading your reply I realized that I left out some pertinent information.

Even though I can run 3 kegs now, I only have two hooked up. One to each regulator. These are the valves I'm using between the regulator and the gas line. The keg that is already carbed is set at 10 psi (for some reason, 12 was just a little too much for this recipe). The new one is hooked up to the other regulator and is now set at 14 psi. You mention that all the kegs would attempt to equalize. But how can that be if I'm using a dual regulator?? If that's the case, what would be the purpose of having a dual regulator with the ability to adjust each on to it's own pressure.

Ok, you are good to go then...

You have a dual regulator so each operates independently... So that's good...

I assume that since you said you 'can' run three that you have a Y adapter on one of the regulator outs...

That's where my dissertation comes in except that you have check valves on the outs of the y-adapter so you should be golden there... ( and hopefully a third on the single out regulator just for completeness and the ability to shut it off downstream )

So... I defer to inky... Gas bottle almost empty and thus not supplying enough overall pressure to carb a keg...

Or... That brew just needs MOAR... (Gas pressure, time... Colder temp.... Etc.)

EDIT: BTW, I find force carbing for about 5-7 days at 20 p.s.i or so works well for me...

Post by **BlackDuck** » Tue Apr 12, 2016 12:44 pm

Thanks guys for all the help!!! I called Keg Connection to get the weight of an empty CO2 tank so I could weigh it tonight. He asked what the problem was and came to the same conclusion as both Inkleg and Papa.....most likely a tank that is close to empty. So I'll weigh it tonight and see what I get. Good thing I have a backup if it is close to empty. I'll just need to swap them out. Keep your fingers crossed.

Post by **Beer-lord** » Tue Apr 12, 2016 12:57 pm

I usually get about 8-9 kegs out of a 5 lb tank. I've never tried to weigh mine but what size do you have and what weight did he tell you?

Anyone know what a full tank should weigh?

Post by **BlackDuck** » Tue Apr 12, 2016 1:10 pm

I have a 5 Lb tank. He put me on hold while he grabbed one and weighed it. Came back and said it was 7.6 pounds. That's with the valve assembly.

As far as a full tank, I'll weigh my backup tonight and post the weight here. But if it's a 5 Lb tank wouldn't that mean a full tank weighs 12.6 pounds???

Inkleg · Post by **Inkleg** » Tue Apr 12, 2016 1:11 pm

Weight is stamped on the tanks. Around 7lbs empty for a 5lb tank + 5lbs Co2 =12lbs for a full tank, more or less. It will look something like TW7 or just W7 in amongst all the letters and numbers.

Inkleg · Post by **Inkleg** » Tue Apr 12, 2016 1:14 pm

Your right Chris, now that I think about it it as 7.6 or something like that.

Post by **Beer-lord** » Tue Apr 12, 2016 1:20 pm

This conversation is starting to come back to me now. I didn't search but I'm sure it wasn't all that long ago and none of us can remember. And I'm older than most of ya'll so you guys have no excuse.

Post by **BlackDuck** » Tue Apr 12, 2016 4:52 pm

I weighed the tank. It's coming in at 8 pounds, 8 ounces. So there is only about a pound of CO 2 in there. Do you think that's enough gas to carb a keg and keep the other one at pressure, or should I just swap out the CO2 tanks?

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BigPapaG · Post by **BigPapaG** » Tue Apr 12, 2016 5:48 pm

Should be fine...

I never change my tank until it's empty...

(ie: weighs about what the empty tank should weigh)

A pound of gas is one fifth the total gas by weight...

I just think that keg needs more time is all...