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Old 10-24-2006, 05:41 PM
Donbecker Donbecker is offline
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Default Balancing calculations...

Gravity:

.45psi / ft.
3 1/2 ft. between bottom of keg and faucet/spout.

3.5 * .45 = 1.575 psi

Altitude:

1psi / 2000 ft. above sea level
Phoenix is 1117' above sea level
1117/2000 = .5585psi

So....

14
- 1.575
- .5585
= 11.8665 psi

3/16" Beer Tubing is 3psi / ft

11.8665 / 3 = 3.995

So I need approx. 4 ft. of 3/16" tubing.

Does this sound right?

My kegerator came with about 5' of tubing on both faucets.

My suggestion to anyone having issues is to do the calculations to get off on a good footing
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Old 10-25-2006, 06:34 AM
darck1 darck1 is offline
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Quote:
Originally Posted by Donbecker View Post
Gravity:

.45psi / ft.
3 1/2 ft. between bottom of keg and faucet/spout.

3.5 * .45 = 1.575 psi

Altitude:

1psi / 2000 ft. above sea level
Phoenix is 1117' above sea level
1117/2000 = .5585psi

So....

14
- 1.575
- .5585
= 11.8665 psi

3/16" Beer Tubing is 3psi / ft

11.8665 / 3 = 3.995

So I need approx. 4 ft. of 3/16" tubing.

Does this sound right?

My kegerator came with about 5' of tubing on both faucets.

My suggestion to anyone having issues is to do the calculations to get off on a good footing
I like getting the calculations right myself... unfortunately I forgot to account for the height above sea level of where I am (Kennesaw GA). I'm from the coast of England and I'm so used to being *AT* sea level I never thought about it - but Kennesaw is over a thousand feet above so I've got to take that half-pound into consideration I guess.

I don't see where you take into account the 1 pound of pressure actually needed to dispense.
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Old 10-25-2006, 04:08 PM
Donbecker Donbecker is offline
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darck1,

Can you refer me to where this is noted?

I'm using the "Balancing a Direct Draw System" guide from MicroMatic...
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Old 10-25-2006, 04:15 PM
darck1 darck1 is offline
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I saw a formula on a couple of other sites...

L=(P-(h*0.5)-1)/R

Where L=length of line, P=pressure you're using, H=vertical lift and R=resistance of the line. The -1 is for the pressure you need to dispense.

I've posted my calculations pretty much all over this site - nobody's told me I'm a crazy wacko yet but then again I've not seen a post from Scott for a while... :-p
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Old 10-25-2006, 07:55 PM
Donbecker Donbecker is offline
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in that calculation, where do you compensate for altitude?
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Old 10-25-2006, 08:11 PM
Donbecker Donbecker is offline
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Well here's some info.

I bought a radioshack thermometer, put the probe in a glass of water inside the kegerator.

It's been reading @ 36.9 for awhile.

I poured a pitcher or two and then stuck the probe in the pitcher.

41.9!!!

So I've been most likely running way way too warm.

So now that I know about the approximate 5 degree difference ( YMMV) we'll get this 1/4 keg of MGD chilled down and see what happens then.

I just picked up a 13.2 of Strongbow cider and a 1/6 keg of Pyramid Hefe.

I cannot for the life of me find someone to call (ie a distributor) to get the CO2 numbers.

Tomorrow I'm just going to call both companies directly and see if I can find someone to help.
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Old 10-25-2006, 08:45 PM
Donbecker Donbecker is offline
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Well, I drove the temp on the radioshack thermometer (while in the glass of water) to about 34.4.

Poured out 2 pitchers and got 38.5.

Like magic about 70-80% of the foam problem went away.

"Getting better all the time..."
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Old 10-26-2006, 06:17 AM
darck1 darck1 is offline
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Quote:
Originally Posted by Donbecker View Post
in that calculation, where do you compensate for altitude?
You don't - the "P" is the pressure you are using on the CO2 tank. That's what you adjust for the altitude. If I'm using 14 as my "P" number then I'll have to dial my tank to umm... is it up or down? Up I think... 14.5 and then use 14.5 in my calculations instead of 14
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Old 10-26-2006, 06:20 AM
darck1 darck1 is offline
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Quote:
Originally Posted by Donbecker View Post
Well, I drove the temp on the radioshack thermometer (while in the glass of water) to about 34.4.

Poured out 2 pitchers and got 38.5.

Like magic about 70-80% of the foam problem went away.

"Getting better all the time..."
Don, I've heard of people getting problems like this with their kegerators because the tower was warm. Some have fixed it by using small fans to blow cold air up into the towers. Look at this thread tower cooling

I constructed a full air-cooled solution for myself because my tower is mounted on a bar away from the converted chest freezer I'm using.
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Last edited by darck1; 10-26-2006 at 06:26 AM.
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Old 10-26-2006, 09:28 AM
Donbecker Donbecker is offline
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Thanks for the reply.

I'm using a DD58: http://www.micromatic.com/keg-refrig...-pid-DD58.html

It has fans inside it with air tubes blowing air up into the towers, the towers are definately cold. When I pour a pitcher I get some condesation on the spout so I think it's ok.
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Old 10-26-2006, 10:22 AM
darck1 darck1 is offline
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Default Temperature

Maybe you just need to let the kegs sit in the cooler longer? Takes a while for a keg to get to the right temp (a lot longer than a glass of water takes).
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Old 10-26-2006, 02:05 PM
Donbecker Donbecker is offline
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Yeah it definately takes longer with pressure and temperature changes.

I just got off the phone with Strongbow...

Strongbow, Wood Chuck Cider, etc. is 18 - 20psi @ 38 - 40 degrees.

I also talked to Pyramid...

Pyramid Hefeweizen is 16-18psi @ 38 degrees.
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Old 11-03-2006, 10:01 AM
darck1 darck1 is offline
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Quote:
Originally Posted by Donbecker View Post
Yeah it definately takes longer with pressure and temperature changes.

I just got off the phone with Strongbow...

Strongbow, Wood Chuck Cider, etc. is 18 - 20psi @ 38 - 40 degrees.

I also talked to Pyramid...

Pyramid Hefeweizen is 16-18psi @ 38 degrees.
Wow... that's high. You'd have to put more restriction in your line to compensate or you're gonna be looking at very fast pours.
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Old 11-08-2006, 06:53 PM
ernestbud ernestbud is offline
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on most of your domestic brews you need to add 1 lb for every 2 degrees above 38 ex if at 42 deg you would need to push it at 14-16 lbs
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Old 11-16-2006, 03:20 PM
beerboy52 beerboy52 is offline
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As far as altitude is concerned Miller Brewing says 1/2 lb of resistance must be added for every 1000 feet of altitude.

Your line length. I would first use the 5 ft that came with it. You should be good with that at 13-15 psi.

Though the 16-18 psi the breweries recommended will work (because you move through it rather quickly. If left to sit in a slower volume place, the beers would become overgassed. If you are going to raise the pressures over the normal brewery level (15 psi) you need more line to suppress the gas bubbles.
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Old 11-20-2006, 07:31 PM
Scott Zuhse Scott Zuhse is offline
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Are we calibrating our Radio Shack thermometer? Adjustment for elevation should take place with the PSIG to the keg. Increase one pound for every 2000' change from sea level. The main reason for this is gauge error due to the decrease in atmospheric pressure at higher altitude.

Once you determine what PSIG to utilize based on temperature of the beer, CO2 vols. and elevation, then the restriction (PSI) against the beer - as it flows through the system - can be determined. Be aware that if these two different pressures in a system equal each other, your flow rate will be approx. 128 oz./min.

So, how many of us actually measure how fast or slow the beer comes out of the faucet? Seems that if we do not accomplish this that this restriction stuff is somewhat useless. Normally catch 15 seconds of beer and multiply this by four. May want to conduct this test at a time when you would want to drink a pitcher of beer (ever a bad time?).

Many techs who work on retail systems that utilize 3/16", will simply get the PSIG to the keg right, install seven to eight feet of 3/16" and then cut back in six inch increments until they acquire flow rate desired by the bartenders.
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Old 11-24-2006, 06:44 PM
jeffreynolds@tampabay.rr. jeffreynolds@tampabay.rr. is offline
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Default Foamy beer

scott

we have a TRUE direct draw beer dispensr. I have 2 1/6 kegs in the cooler. Bus Slect and Ship yard ale. On the pour the beer comes our very foamy but goes away somewhat quickly. the c02 is set to 11 psi. help.

jeff
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Old 11-27-2006, 07:24 AM
ernestbud ernestbud is offline
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1.What is the actual temp of the beer liquid
2.what type of glassware are you using chilled-frozen- or room temp
3 what is the length and size of your beer line
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Old 11-27-2006, 08:30 AM
edramshaw edramshaw is offline
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In addition to ernestbud's questions:

Is the tower coming up from the cooler with the taps chilled? (Usually there is a hose with a blower pushing cold air up there). The absence of this often creates problems similar to what you describe because the beer sitting up in the tower warms creating and initial burst of foam.
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