Natural Gas & Turkey Fryers & big wok burners

g_rodriguez

Just found this place on the web, and boy am I glad. I need some counsel which is surely available here.

I picked up a natural gas wok burner that I hoped to retrofit into a propane turkey fryer that I use outdoors to boil maple sap into syrup and occasionally brew some beer. My plan was to install one of those quick-connect fittings outside my house and use a flexible line to feed the thing. I have a fair bit of experience with black pipe & natural gas -- I'm not concerned about the plumbing per se; if I need more than 12' of pipe to get the job done I will be surprised.

The wok burner I bought is a chunk of cast iron fitted with 32 individual jets, and rated for 160k BTUs. I confess I was not expecting the size & weight of the thing. I was also surprised to see it sized to accept 3/4" NPT. This is when my confusion started.

The facts (as I know them):
- I'm confident I have 7" WC coming in to the house. We got an upsized gas meter several years ago when we installed a 150k btu pool heater, but am not sure about the meter's actual throughput. All of the interior gas-consuming appliances (furnace, water heater, clothes dryer) are clustered near the end of a 40ish foot run of 1" black pipe with a couple of right angle turns.
- The branch line that I was going to extend to the outside of the house is 1/2" black pipe, also near the end of the line inside the house.
- The hose kit I have contains a 3/8"NPT quick-connect fitting for one end, and a 3/8" flare fitting for the appliance end.

My questions:
- Do I need a regulator in the line that feeds the disconnect fitting? If so, what output value do I need? (or is this even a sensible question?)
- Is the flexible line kit (all 3/8") insufficient to feed this burner? (I'm thinking it is) Is there a better, safer way to feed this burner?
- What options are available to adjust the flame once lit? Is it ok to use a ball valve for this? I'm not sure what to search for online.

This rig will be used only occasionally: In the spring when the maple sap is flowing, I might use it five or six times over the course of a 2 - 3 weeks. Brewing beer might happen two or three times a year. My current gas grill is propane and used infrequently (90% of my outdoor cooking is over charcoal), I don't plan to use this line to ever feed a grill.

YouTube is full of people who are using burners like this with terrifying-looking hookups. I want to be safe and do this the right way. If that means sending the wok burner back and getting a smaller one (23 jets, 100k BTU, 1/2"NPT input), then I'm ok with that. Likewise, if a larger diameter flexible line kit can be had, then I will search it out.

Thanks, folks.
Greg

Zman

Does the manufacture offer a propane conversion kit?
Your first challenge is going to be finding 32 orifices that are sized for propane (much smaller). 

g_rodriguez

My apologies. I get so distracted and type so much detail in posts that I tend to obscure things.

The fryer in question is propane now. I want to replace the current burner with a natural gas wok burner fueled by a quick-connect NG line from the house. I already have the burner, but it has a 3/4" NPT inlet, which surprised me. I can easily install a 1/2" black pipe line, but the flexible NG line I have turns out to only be 3/8" ID. I just need to nail down the details to do all this safely.

I'm working on getting the details & sketch you asked for in your first post, Youngplumber. I appreciate the willingness to help.

retiredguy

Those gas orfices look exactly like the orfices in a Bryan Atmospheric Boiler. If your search for the correct orfices does not produce results, I would do a search for a Bryan Steam Boiler rep in your area and ask if they could supply the orfices you need. In Pittsburgh, the rep is James S Gunst Company at 412-487-8484. He is very knowledgeable and should be able to help. I have in the past, if the correct orfices were not available, soldered in the orfices and re-drilled them for the orfice size needed. Bryan Boilers is located in Peru, Indiana 765-473-6651 My 2 cents.

Tim Potter

Google search this:

MENSI Propane LP Natural Gas Brass Jet Nozzle Sparyer for 10, 20, 23, 32, 44 Tips Cast Iron Burner Set of 4 (Natural Gas Burner Nozzle)

It looks like the LP Orifice size is: Injector jet small hole: 0.7mm (0.028")
The Natural Gas orifice size is: Injector jet small hole: 0.9mm (0.035")

they are 8.98 for a pack of 4 on amazon


Tim

ChrisJ

You need to be careful with the flex hose.  They are rated for a certain btu/h with a certain amount of pressure drop.

For the size burner you're talking I would expect a 1/2" hose minimum.  A Sturgis 1/2" hose is rated 135,000 bruh with a 1" drop if you can tolerate that much drop.

Their 3/4 hose is rated 275,000 bth with 1" drop

That 3/8 hose would only be good for 60,000 best case.



Do you know what pressure your house is running at?  Do you have regulators at each appliance?

Zman

The problem you may run into is that Natural gas contains ~1,000 btu/cf and Propane contains ~2,516 btu/cf. To make the conversion you will need larger orifices right out of the gate. You may need to upsize or adjust the regulator and perhaps the hoses as well. You need need the extra flow and must overcome the resistance that comes with the higher flow.
It is easiest to buy the conversion kit from the manufacture and let them do the brain damage. You can reverse engineer this it just takes more research.
Chances are your house is running 7" WC pressure for natural gas. the regulator at the meter will confirm.

Zman

An orifice drill is also a very affordable alternative.
Do your existing orifices have a number stamped on them?

g_rodriguez

Firstly, thanks to all for taking the time to read and comment. I appreciate it.

After sleeping on it I've decided to return the monster burner and purchase a smaller size: 100k BTU, 23 natural gas jets. It's also threaded to accept 1/2" NPT input (instead of the 3/4" on the one I have). I'm locked in to a 1/2" black pipe NG supply line from the house to the outdoor quick-connect fitting. I don't want to have a perpetually fuel-starved burner.

ChrisJ said:

For the size burner you're talking I would expect a 1/2" hose minimum.  A Sturgis 1/2" hose is rated 135,000 bruh with a 1" drop if you can tolerate that much drop.
Their 3/4 hose is rated 275,000 bth with 1" drop

That 3/8 hose would only be good for 60,000 best case.
Do you know what pressure your house is running at?  Do you have regulators at each appliance?

This is very informative, thanks! I will ditch the 3/8" hose and get something bigger. I've been tying (unsuccessfully) to talk to someone from my gas company. I'm pretty sure we're at 7" at our gas meter, but the only thing I've been able to find is a vague statement on their website that says their 'standard domestic pressure is 1/7#", whatever that means. We don't have regulators at any of the appliances (furnace, water heater, clothes dryer).

ChrisJ

g_rodriguez said:

Firstly, thanks to all for taking the time to read and comment. I appreciate it.

After sleeping on it I've decided to return the monster burner and purchase a smaller size: 100k BTU, 23 natural gas jets. It's also threaded to accept 1/2" NPT input (instead of the 3/4" on the one I have). I'm locked in to a 1/2" black pipe NG supply line from the house to the outdoor quick-connect fitting. I don't want to have a perpetually fuel-starved burner.

ChrisJ said:

For the size burner you're talking I would expect a 1/2" hose minimum.  A Sturgis 1/2" hose is rated 135,000 bruh with a 1" drop if you can tolerate that much drop.
Their 3/4 hose is rated 275,000 bth with 1" drop

That 3/8 hose would only be good for 60,000 best case.
Do you know what pressure your house is running at?  Do you have regulators at each appliance?

This is very informative, thanks! I will ditch the 3/8" hose and get something bigger. I've been tying (unsuccessfully) to talk to someone from my gas company. I'm pretty sure we're at 7" at our gas meter, but the only thing I've been able to find is a vague statement on their website that says their 'standard domestic pressure is 1/7#", whatever that means. We don't have regulators at any of the appliances (furnace, water heater, clothes dryer).

How long is the 1/2" pipe?
How much piping is going to be in between your new burner and the meter? Include elbows etc.
This is very important because a very short 1/2" pipe can supply a lot of gas but a very long 1" with a lot of turns cannot.

It's a function of pipe length, turns etc and pipe size.

g_rodriguez

ChrisJ said:

How long is the 1/2" pipe?
How much piping is going to be in between your new burner and the meter? Include elbows etc.
This is very important because a very short 1/2" pipe can supply a lot of gas but a very long 1" with a lot of turns cannot.

It's a function of pipe length, turns etc and pipe size.

I got started yesterday making a diagram of the whole system to post, but was sidetracked by work. Here are my notes (the entire system is black pipe):
- The regulator at the service entrance outside the house is unmarked as far as I can see, but the meter is labled 250 cfh @ 1/2". I have 1" pipe exiting the meter and entering the house. That turn is actually a T fitting with a 1" branch entering the house and a 3/4" branch going back underground to feed a 150k btu pool heater ~25' away.
- Inside the house I have about 37' of 1" pipe before the first appliance with a total of 3 90 degree turns in that run (including the T fitting outside). All the feeds to my appliances are within the next 4 feet.
- First appliance feed is to a 80k BTU furnace - starting with a 1" x 1/2" x 1" T, feeding ~ 9' of 1/2" pipe with five 90 degree turns (including the T).
- Second feed: 38K BTU water heater - 1" x 1/2" x 1" T, feeding ~ 7' of 1/2" pipe with 3 total bends
- Third feed: currently a capped-off 4' long stub of 1/2" pipe with two bends. This is the line I would extend another ten feet or so (probably with no additional bends), to the exterior of the house to a quick disconnect fitting to feed the burner I want to use. This used to feed a 30k btu vent free heater in the garage, but that's gone now.
- Fourth feed: clothes dryer (unknown BTUs, but it's a newer front loading Samsung) - 1" x 1/2" reducing coupler followed by 7' of 1/2" pipe with only one 90 degree bend.
- Also, there are no external regulators anywhere in the system that I can see.

Regarding the line I want to extend (third feed above), I'm not completely against swapping that out for a 3/4" line. It's within my abilities. It's just a bigger job than I'd contemplated so far. Also, we don't currently have a gas range, but this line would run directly under the range in the kitchen. If I do this I'll probably install a stub up behind the range for house resale purposes.

ChrisJ

Youngplumber said:

You need the heating value of your NG. It comes in 1000 1100 and 1200 btu per cu ft. Some people just use 1000 to be safe which is fine. Yours may come in a value different than one of those I've not heard of it but there are lots of things I've not heard of. 

Not really relevant here.
It is what it is.

g_rodriguez

I found this on a detailed excel spreadsheet I downloaded from my gas company's website (nicor gas in Illinois).

BTU Per Cubic Foot
By Calorimeter 1055
Calculated from Analysis 1052

Specific Gravity
Determined by Balance 0.605
Calculated 0.603

Charlie from wmass

Use 1000 BTUs per cubic foot and you will be fine for 90% of the systems in North America. Unless somebody is micro engineering a job and using the full BTU and gas pipe sizing formula it won't matter. 

Charlie from wmass

I would rather run the inch and a quarter pipe because next week the supply and gas could drop in BTUs per cubic foot and then we would have a low gas supply issue with the appliances. The labor difference and the material difference is negligible when compared to having sooted up appliances and having to walk back to a customer and explain to them why we have to repipe a whole section of their house. It's called being pennywise and pound foolish. 

Charlie from wmass

Or we can you longest length charts based on 1000 btus per cubic foot.

Zman

Charlie from wmass said:

Use 1000 BTUs per cubic foot and you will be fine for 90% of the systems in North America. Unless somebody is micro engineering a job and using the full BTU and gas pipe sizing formula it won't matter. 

I agree. The other 10% has the opposite problem. At 10,000' they only give you ~713 btu/cf so the appliances will burn better with less air density. Go figure...

Zman

@Youngplumber , you sure have yourself worked up on this one.
Since you asked, it won't work. The meter is too small and when everything is running the pressure will drop.
The piping in the house is too small and adding another 100k at the end of the line is going to make the pressure drop even more. It really doesn't matter what size the last chunk of pipe or hose is on the end or if the BTU content is 1,000 vs 1,052 vs 1,200, if you run the numbers on this, there is no way it checks out per code.

Personally, I would buy a couple bottles of propane and save myself the brain damage.

Zman

Those guys are pretty sharp. I have learned a great deal from both of them.

Gordy

Maybe we should touch on how much the 250k meter will supply with 150k pool heater, 40k water heater, furnace, dryer, stove?

plus 160k burner.

So long as it’s summer, and pool heater is off. Be fine. User conditions of wok burner warranted in the equation. What’s all the possibilities of gas appliances running while Woking......

The other is getting burner converted to see what output you end up with.

Error on the size of larger in gas piping. Bigger is better, as has been conveyed. Material cost is negligible.

Oh yes some have been doing this for 40 years. Embrace the knowledge, and  Learn from it.

g_rodriguez

Wow... this conversation is very informative. I appreciate everyone's energy and insights. I learned a lot:

- The NG service in this house was apparently sized to supply exactly what was here when it was built (furnace, water heater, dryer) and barely a thing more.
- I shouldn't even think about a tankless water heater when this one goes out.
- I'll keep buying propane to make my beer and maple syrup (the wok burner got returned yesterday).

The house was built in '88. To be fair, things like 200k BTU tankless water heaters weren't on the horizon then, but the gas service turns out to be one more thing that is just *barely* adequate: the power was 100 amp (which I changed over to 200) and water main is 3/4" copper. None of the utilities were installed with any growth in mind. Just *one more* thing the builder cheaped out on in my view. I cuss his name at least once a week - no joke.

I conceived this project because it takes about 5 - 6 hours and 3/4 of a tank of propane to boil 5 gallons of maple sap down to 16 ounces of syrup with my current setup. The wok burner was intended to make it faster, natural gas to make it more convenient. I suppose I could get a propane fueled wok burner and get a bigger tank so I have fewer refill runs. I could also go forward with putting in a 3/4" line and have few, if any problems; the odds of multiple appliances firing at once are slim to none. I'll probably just stand pat, and keep doing what I'm doing.

And yes, I realize this adds up to way more than simply buying real maple syrup. The Mrs. really enjoys giving the syrup from our trees to friends & family. So I keep getting propane refills.

In any case, we'll be looking to sell this place in the next couple years and put IL in our rearview mirror once & for all. I don't want to chance having to jump through hoops before a closing because some home inspector has the NFPA memorized.

Thanks again, all. I appreciate everyone's time and energy.

Charlie from wmass

@g.rodriguz the short answer is that your gas supply will not be able to power that even in the best of conditions unless you shut down other equipment. The most critical number that you need is the distance along the run of the pipe from the meter to the farthest Appliance. The main line has to be sized according to that. Every one of those orifices needs to be removed from that burner and you need to buy a pressure regulator. Can you get me the other day with you you also will not have much control when trying to boil the sap with that burner. It would be perfectly good if you wanted to melt lead with it. Making maple syrup is definitely a labor of love not a lesson in economics. That's the main reason why in my 49 years I have never made maple syrup. In Berkshire County Massachusetts many of the small-scale maple syrup producers use wood fired equipment for making maple syrup because they buy slab from the local sawmills for about the cost of trucking. I would suggest returning that Wok burner and looking for something more in the 30,000 BTU range. Maybe even buy a turkey fryer and use the propane. Interlocking this with your home gas distribution system is fraught with issues. Discussion of the BTUs per cubic foot it's truly not relevant to your situation.

Erin Holohan Haskell

Youngplumber said:

There you have it. Run 1-14" to everything including your turkey fryer. It save you money says @Charlie from wmass forget the piping you have. Your gas heating value. Forget the pressure you have too. That could all change.

We should all just eat bananas and swing from trees. It takes nothing to do this for a living. 

@Youngplumber, our #1 rule here is to be respectful of others. Your nasty and sarcastic comments throughout this thread are in direct violation of that. If you can't share your opinions without attacking other members in the process, then you'll no longer have access to this forum.

ethicalpaul

My favorite Maple syrup place in the adirondaks uses reverse osmosis to get most of the water out, then boils off the rest. I had a chance to talk the owner about it. I know he's not unique in this. Might be worth looking into. He started as a hobby and now I think he makes his whole living from this.

My friends back in Michigan who do it on a hobby level use wood because they have it on their land anyway and it's basically free plus labor.

Good luck in your hobby!

g_rodriguez

@ethicalpaul , I looked briefly at using reverse osmosis in maple sugaring, and that looks amazing! Thanks for the tip!