Gas plumbing

I have three banjo burners that are 210,000 btu's each. I am getting black steel tube for the gas line and the. I want to come off the t's with the plastic yellow flexible gas line. But it looks like the 3/8" hose is only rated for 33,400 btu's per hour. Is this going to be a problem?

It sounds like you wouldn't get full use of your burners with that hose...I also wanted to note that I think those flexible hoses are for equipment that is not meant to be moved around like a home brew system is. I would stick to the hose connections that are for BBQ grills. You can buy these at different lengths on line

Just my thoughts...

ox1574 said:

I have three banjo burners that are 210,000 btu's each. I am getting black steel tube for the gas line and the. I want to come off the t's with the plastic yellow flexible gas line. But it looks like the 3/8" hose is only rated for 33,400 btu's per hour. Is this going to be a problem?

Click to expand...

The yellow flexible gas lines are most likely plastic coated steel. Check out this chart for info on sizing vs btu's:

(scroll down the page some to locate the charts:

http://www.plumbingsupply.com/gasconnectors.html#BTUS

Also, check out this table showing max BTU draw from various sizes of propane cylinders:

http://www.flameengineering.com/Propane_Info.html

It depends on the tank temperature, but @ 70 deg F, the limit is about 92.000 btu's/hr. What this means is that unless you use a larger cylinder or somehow cascade multiple smaller cylinders, you will never be able to supply 200,000 btu/hr of fuel to the burners regardless of their max rating. Running more than one of the banjos simultaneously will make the problem even worse.

It is also unlikely that you will be running the banjo WOT. Those burners put out a huge amount of heat and at WOT, much of that heat would be lost out the sides of the burner. You would also be wasting a lot of fuel at the same time.

IMO, the 3/8" ID flexible gas line would be more than large enough for your burners. Please do not rely on what I have posted above as I am not at all an expert on this stuff.

From my LP Sevicemans manual
Vaproization rate for 100 lb cyl

lbs LP Ambient Temp 40F 60F 70F
80 BTU x 1000 180 214 236
60 140 176 192
40 105 131 141

As you can see as you lose volumn and temp you lose potential BTU in a hurry. Using a 20lb bottle would significantly reduce your BTU potential.

Hi pressure line sizing (10 PSI system)
copper tubing 10' run 20' run
3/8" 558k 383k
1/2" 1387K 870k
Steel pipe
1/2" 3339k 2295K

2nd stage line capacity @ 11" WC or 1/2"psi
Copper tubing
3/8" 49k 34k
1/2" 110k 78k
Steel Pipe
1/2" 281k 200k

My manual doesn't address the corrugated flex lines but the currugation will create a significant flow loss due to turbulence in the line.

Well most of that is Greek to me. After standing in home depot for an hour or two, I was going to use 1/2" black steel pipe, then the hd guy talked me into 3/4" black pipe with the 7/8" od yellow flex line. I believe the banjo burner fitting that comes with it is 3/8", so I don't know how I would go from the 7/8" down to 3/8". I am wondering if I will be good with the 1/2" pipe and 3/8" flex line. I will be running two burners at once, and possibly three at once for a short amount of time. Arggh...this gas stuff is frustrating.

ox1574 said:

Well most of that is Greek to me. After standing in home depot for an hour or two, I was going to use 1/2" black steel pipe, then the hd guy talked me into 3/4" black pipe with the 7/8" od yellow flex line. I believe the banjo burner fitting that comes with it is 3/8", so I don't know how I would go from the 7/8" down to 3/8". I am wondering if I will be good with the 1/2" pipe and 3/8" flex line. I will be running two burners at once, and possibly three at once for a short amount of time. Arggh...this gas stuff is frustrating.

Click to expand...

IMO, the HD guy is an idiot. The 1/2" rigid black iron pipe would be more than sufficient and the 7/8" flex line is way overkill for this application. Just look at the size of the orifice that the gas must pass through as it enters the burner and I think this will become obvious. You will be fine using the 1/2" rigid pipe and the 3/8" flex line.

Never mentioned nat gas or lp.

It was very easy to infer.

I use 1/2" black pipe to 3/8" flex line without any problems. I use two Blichmann NG burners and like others have stated; they put out more than enough flame. You will never use them wide open or you'll have flame out the sides and waste a great deal of gas.

Thanks guys. Looks like I will go back and get the 1/2" pipe and 3/8" flex. As for the propane tank connection to the 1/2" pipe what do you guys use? And where can I get a 5'-10' hose to go from the tank/regulator to the 1/2" pipe?

Try these guys: http://www.flameengineering.com/Hose.html

I went with these. Not sure if they are the best or not but they work fine with my BG 14s. I also used one to connect the HP regulator to the pipe.

http://www.agrisupply.com/product.asp?pn=36108&cn=5400001&bhcd2=1297871344

Are you running HP or LP propane?

I am running LP.

Same question for what pressures you're going to run. That yellow flex line at Home Depot or Lowe's is usually rated for appliances up to 11"WC. If you're running your burners on low pressure, it should be fine.

I am about to do a set up with two banjos, myself. What did you end up using from the BIP to the burners?

I used 1/2" black iron and the stainless steel flexible appliance connectors without any problem.





There are many more in my build thread.

https://www.homebrewtalk.com/f51/first-sigle-tier-brew-rig-290115/