Tips for a propane manifold

I am building a single tier system similar to JonW's and have a question about my gas lines. I am thinking about using one inch black pipe for the main manifold and then half inch for the lines to the burners. Is one inch too large? Also, do I need to worry about purging the line after a brew since there will presumably be a fair amount of propane left in the pipe?

You are over thinking it (IMHO). I used 3/8 for everything, and it works great (mine uses 2 turkey fryer burners and a 10 psi reg).

lgoolsby said:

I am building a single tier system similar to JonW's and have a question about my gas lines. I am thinking about using one inch black pipe for the main manifold and then half inch for the lines to the burners. Is one inch too large? Also, do I need to worry about purging the line after a brew since there will presumably be a fair amount of propane left in the pipe?

Click to expand...

I used 1/2" I think, cause I couldn't find 3/8, then ran a reducing bushing to connect the hose to. After I shut off the propane but before I disconnect the tank, I open the ball valves to dump the little bit left in there, no explosions yet.

I used 1/2" then branched off to each burner with 1/4". It works fantastic.

Simple answer is ½” black pipe should be sufficient.

Long answer depends on a lot of variables that cannot be answered without knowing your specifics. Burner size, location of regulator, high pressure or low pressure, distance between regulator and burner, etc. The higher the pressure the smaller the pipe required.

My system has two BG14 low pressure propane burners and my manifold is ½” pipe. I use 5/8” stainless flexible whips that connect the burners to the manifold. My 11”WC regulator is located roughly 5’ from burners. It’s better to oversize than undersize.

There are charts online that will help you calculate your pipe size based on pressure, distance and required BTU’s.

MaxOut said:

Simple answer is ½” black pipe should be sufficient.

Long answer depends on a lot of variables that cannot be answered without knowing your specifics. Burner size, location of regulator, high pressure or low pressure, distance between regulator and burner, etc. The higher the pressure the smaller the pipe required.

My system has two BG14 low pressure propane burners and my manifold is ½” pipe. I use 5/8” stainless flexible whips that connect the burners to the manifold. My 11”WC regulator is located roughly 5’ from burners. It’s better to oversize than undersize.

There are charts online that will help you calculate your pipe size based on pressure, distance and required BTU’s.

Click to expand...

I will be running three 23-tip jet propane burners producing around 190k btu's. I was planning on having the burners ~5 inches from the bottom of the kettles. The total length of the manifold would be around six feet and I have a regulator reducing the propane from tank pressure to low pressure.

If someone could point me to the online tools I would appreciate it.

1/2" is more than adequate and 3/8" is likely fine as well. All you'll do with 1" is waste a lot of gas. If I had to do it over again I would have tried to find 3/8" or even 1/4" and I run three burner simultaneously with pilots. 1/2" takes time to bleed air.

Here are a few charts.

How many burners? Size your pipe based on your combined max BTU's. 3/8" will be too small if you are running more than one burner at 190K BTU's. Also keep in mind that your regulator has to be rated for the max BTU’s as well. ½” black pipe is easy to find and inexpensive. Will it work on undersized pipe...sure but you will not get the max BTU's and with jet burners it is important to keep pressure consistent to avoid a situation where you have incomplete combustion and produce excessive amounts of carbon monoxide. Blue flame good, yellow flame bad.

As far as wasting gas I’m pretty sure that’s not a major concern based on your choice of 190K BTU burners. To avoid excess fuel left behind in the manifold turn off the gas at the tank while the burner is still lit and burn off the gas left in the pipe. I have shut off valves before regulator and at each burner.

Using 1/2" line at the stand with good needle valves gets you plenty of heat/flame.