high pressure vs low pressure orifice...

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J-Malone

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I just want to know the difference between the two orifices. Can I drill a LP orifice and make it high pressure? Or is it the other way? I am build a stand and I am at the gas manifold stage as you might have guessed. Any help us greatly appreciated ...
 
I don't think its either. The regulator determines the pressure. Some stoves are able to switch between low pressure LP and low pressure NG by changing out the orifice. In that case, NG is bigger.

There are a few stoves that people have mentioned can be low or high pressure (such as the hurricane) but I haven't seen anyone actually verify that. They just "look" alike. Let me see if I can find an example.

EDIT: Here you go

High Pressure:
http://www.alliedkenco.com/catalog/product_info.php/cPath/30_718/products_id/2390

Low Pressure:
http://www.williamsbrewing.com/HURRICANE-LOW-PRESSURE-BURNER-NO-STAND-P2677.aspx

If you ask me, these look like the same burners but are being sold differently. Also, the high pressure says 155K BTU and the low says 60K BTU
 
I don't think its either. The regulator determines the pressure. Some stoves are able to switch between low pressure LP and low pressure NG by changing out the orifice. In that case, NG is bigger.

There are a few stoves that people have mentioned can be low or high pressure (such as the hurricane) but I haven't seen anyone actually verify that. They just "look" alike. Let me see if I can find an example.

EDIT: Here you go

High Pressure:
http://www.alliedkenco.com/catalog/product_info.php/cPath/30_718/products_id/2390

Low Pressure:
http://www.williamsbrewing.com/HURRICANE-LOW-PRESSURE-BURNER-NO-STAND-P2677.aspx

If you ask me, these look like the same burners but are being sold differently. Also, the high pressure says 155K BTU and the low says 60K BTU

That is interesting...I was under the impression that you could make banjo, hurricanes, or the 6" Bayou classics into either Hi or low pressure by just changing the orifice and making sure you were providing enough pressure through the regulator?

I am using the 6" BG12 which I got from Agrisupply in the low pressure version. I had a 0-10 psi regulator on hand and when I went to fire them up last night, I couldnt get more than a tiny blue flame from each little hole, no matter how high I turned the regulator or the gate valve...

I was thinking about getting the Hi pressure orifice and upgrading to a 0-30 psi regulator, or would the 0-10 work better with the hi presssure?

I know it seems counter intuitive but I was thinking that HP needed lower regulator pressure (10-15) and that Low pressure needed the 30 or so psi? Am I wrong?

Definitely need clarification..

thanks
 
The orifice opening is larger for the low pressure gas to allow the proper flowput since the psi is normally around 3 to 6.

For LP, the pressure in the tank is in the range of hundreds of PSI and is reduced to 10 to 30 and then forced through a smaller orifice at a higher velocity to improve gas to air mixture.
 
The orifice opening is larger for the low pressure gas to allow the proper flowput since the psi is normally around 3 to 6.

For LP, the pressure in the tank is in the range of hundreds of PSI and is reduced to 10 to 30 and then forced through a smaller orifice at a higher velocity to improve gas to air mixture.

Thanks. But I still would like to know if I should go with a higher psi regulator for the low pressure to get the flames going or is there another issue?

My setup is pretty simple

tank-->10psi reg-->1/2" black iron pipe-->tee-->gas ball valve-->gate valve-->Low pressure orifice-->BG12 burner

I open the ball valve, open the gate up and turn psi all the way up, I can hear the pressure increase from the tank but it doesnt seem to affect the flame.

I will take a video tonight to show the flame I am getting, it is just what you'd get as you are lighting it w/o much pressure at all and it will not get larger or more intense. Just little blue bubbles on top of the burner holes.
 
I am working on this problem right now too ! I have a meeting at 8am with our local propane tech .. I'm using two burners that are each 3x7 inch rectangles with similar holes as the pics you posted... So far I've tried low pressure (.5psi) and it looked like a candle flame, and 15psi which made a good noise and shot 12" flames, but they were mostly yellow and made a ton of soot, which makes me think the whole thing is running too rich and needs a smaller orifice -- I'll let you know in the AM !
 
The gas jet size is based on pressure and Btu's of gas delivered to burner. Higher the pressure the smaller the opening to maintain needed gas flow. Also the higher the pressure the faster the gas exits from the opening and more air gets drawn in to mix and make larger flames. When you reduce the pressure the flow slows down and the air is reduced along with total burner output. You can increase the gas jet opening size but there is a limit on how much air it can pull in to mix. Usually the burner output is cut by half when pressure is reduced from 10 Psi to .5 Psi because of lower air flow into burner. For the typical 6" burner on .5 Psi LP the jet needs to be 1/16", for the 10" burner 5/64"-3/32" works well. If going to even lower pressure NG the 10" burner is probably the smallest you want to go with either the NG valve adapter or a 3/32"-1/8" opening in the gas jet.
 
Thanks kladue ! That's the most exact answer I've gotten so far ! any idea what should I shoot for as an orifice size with a 15psi reg ??
 
Here is a pic of a high pressure propane and and Natural gas orifice side by side, hope this helps.

brewrig003.jpg


Natural gas is on the right.
 
Here is a high pressure orifice chart http://www.joppaglass.com/burner/highp_chart.html. Based on the description of 3" X 7" burner probably a good idea to start with a #62 bit and get larger after testing for clean flame with air shutter 90% open. Best thing would be to buy an orifice fitting for the 6" burner or one of the 4" burners to start, then drill larger openings if air shutter is 50% or less open to get clean flame.
 
Flame looks good, the yellow streaks are from paint and other contaminants in the burner. The flame lifting above the burner surface is from too much gas/air flow because burner orifice is a bit big for the pressure. Turn the flame down until the light blue portion is touching the burner and then let them run a bit to burn in the paint. After burn in then adjust the air shutter until the very top of the flame starts to show a hint of yellow, this is the point where just enough air is mixing with the gas for complete combustion.
At this point a larger high pressure regulator is not going to help as you already have too much flow now, you would be better off using a Marshall 290 low pressure regulator to feed the gas manifold. With low pressure gas you will get more adjustability of the flame and still get maximum fire possible with those burners. With the low pressure approach you can use furnace valves for automation later without having to make many changes as regulator and burners are already setup.
 
Flame looks good, the yellow streaks are from paint and other contaminants in the burner. The flame lifting above the burner surface is from too much gas/air flow because burner orifice is a bit big for the pressure. Turn the flame down until the light blue portion is touching the burner and then let them run a bit to burn in the paint. After burn in then adjust the air shutter until the very top of the flame starts to show a hint of yellow, this is the point where just enough air is mixing with the gas for complete combustion.
At this point a larger high pressure regulator is not going to help as you already have too much flow now, you would be better off using a Marshall 290 low pressure regulator to feed the gas manifold. With low pressure gas you will get more adjustability of the flame and still get maximum fire possible with those burners. With the low pressure approach you can use furnace valves for automation later without having to make many changes as regulator and burners are already setup.

Thanks for the help. I am using a 10psi regulator and it was fully open, should I possibly turn that down to limit the flow a little bit or just adjust the gate valve a little and leave the regulator on full blast?

Is there a big BTU difference between the Hi and low? I want to make sure that boiling in the kettle wont take forever. I am planning on mostly 6 gallon batches (7.5 pre boil volume), but thinking that I would be mixing in some 10 gallon batches along the way.
Would adding a High pressure valve to the BK burner increase the btus and make it boil faster?

Sorry for the nooby questions but I am not a gas guy...
 
This thread name sounds dirty...sorry had to

lol...I giggle everytime I say or write orifice...I am way too immature for 33...

Love your reviews on YT, btw...and the Mikeller you just did that was flat, I saw a bunch of others that were very carbonated and I think you got a crap bottle...very sad to see what was probably a great beer have to be dumped...ever thought about getting a carbonation cap and putting the flat beer into a 2L bottle or something like that and carbing it w/ co2?
 
I would suggest lowering the regulator pressure and try to get the pressure down to a point where the valves have to be nearly fully open to get the flame to lift off the burner. More pressure is a waste of time as you will just have to close the valve more to regulate the flame and keep it from lifting off the burner. The lower operating pressure will make fine tuning the valves easier when setting flame size as the change in the size of the opening in the valve has less effect. Switching to high pressure gas jet will make regulator pressure more important and valve adjustment more difficult as the gas flow needed is reduced with increased pressure.
You are going to find that the 6" burners will do about as much work as the larger burners as the bigger the fire under a keg, the greater the amount of flame up the sides that does not do anything other than burn things up and boil the sight glass.
 
I would suggest lowering the regulator pressure and try to get the pressure down to a point where the valves have to be nearly fully open to get the flame to lift off the burner. More pressure is a waste of time as you will just have to close the valve more to regulate the flame and keep it from lifting off the burner. The lower operating pressure will make fine tuning the valves easier when setting flame size as the change in the size of the opening in the valve has less effect. Switching to high pressure gas jet will make regulator pressure more important and valve adjustment more difficult as the gas flow needed is reduced with increased pressure.
You are going to find that the 6" burners will do about as much work as the larger burners as the bigger the fire under a keg, the greater the amount of flame up the sides that does not do anything other than burn things up and boil the sight glass.

Thanks, Kladue. I will make the adjustments you suggest. I am hoping to have the system up a running in the next couple weeks.
 
I think it's important to point something out; something intimated but not said directly. Forgive me if I'm stating the obvious.
There is more to switching from high to low pressure than changing the orifice. In order to have a low pressure system you need a low pressure supply. Low pressure LP runs at 11" water column, or a little less than 1/2PSI. 10 PSI is considered high pressure, so right now you're running a high pressure supply through a low pressure orifice. if your regulator is adjustable, you might be able to crank it down far enough to get an acceptable pressure, but you'd be better off getting a proper low pressure reglator. That, or switch to high pressure orifices.
 
I think it's important to point something out; something intimated but not said directly. Forgive me if I'm stating the obvious.
There is more to switching from high to low pressure than changing the orifice. In order to have a low pressure system you need a low pressure supply. Low pressure LP runs at 11" water column, or a little less than 1/2PSI. 10 PSI is considered high pressure, so right now you're running a high pressure supply through a low pressure orifice. if your regulator is adjustable, you might be able to crank it down far enough to get an acceptable pressure, but you'd be better off getting a proper low pressure reglator. That, or switch to high pressure orifices.

I appreciate you pointing this out. I was wondering. I may pick up a low pressure regulator at Lowes this weekend, they arent that high and see if it makes a difference. The 10psi reg I have now is adjustable and I was able to crank it down tonight and it looked even smoother than last night...

Thanks,
 
I appreciate you pointing this out. I was wondering. I may pick up a low pressure regulator at Lowes this weekend, they arent that high and see if it makes a difference. The 10psi reg I have now is adjustable and I was able to crank it down tonight and it looked even smoother than last night...

Thanks,

Your flame looks ok to me. I'd be interested to know how softly you can run it though. It's got a great flame for heating and getting to boil, but I'd like to see/hear how it does for just simmering or maintaining a mash temp.
 
Your flame looks ok to me. I'd be interested to know how softly you can run it though. It's got a great flame for heating and getting to boil, but I'd like to see/hear how it does for just simmering or maintaining a mash temp.

I tried this last night. I turned the regulator down to a very low pressure and was able to really adjust the burners to a low simmering type flame and like you said something I could use during mash recirculation to maintain or raise temp slightly

It lost all that windy roar that it had on the lowered setting. I am thinking that I am going to have a very wide range of adjustability. I am still thinking about getting some HP orifices and seeing what they do...just to have the option:ban:
 
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