gas pipe plumbing....the right way

[BucksPA]

any tips i should know about gas plumbing. I'm using the 8 tip jet burners on my system and am using 1/2" black gas piping with unions, tees, valves, etc. there will be alot of connections and this concerns me.

i got the gas rated teflon tape, have some pipe wrenches and plan on tightening the pipes and fittings with great force. other then searching for leaks after everything is tightened, can you think of anything else?

is there any non-permanent sealer i should apply as well?

 

[MMTG]

sounds good! That's what we did for our brew rig.

 

[Thirteen]

I prefer using a pipe dope to teflon tape but that's mostly because it's what I do at work so it's second nature.

As for the assembly... You should have 10 threads on your pipe. When assembling a fitting you should be able to screw it on by hand with relative ease for three threads. Tighten four more turns with a wrench leaving three threads exposed. The threads should then be providing a good seal.

 

[GNBrews]

Pressure test with a concentrated dish soap solution after final assembly.

 

[sjlammer]

I just moved my gas line in my kitchen. I read that you should not use teflon tape. the tubes of pipe dope are fairly cheap, and supposedly work better. good luck

 

[Bobby_M]

The reason regular teflon tape is frowned upon is that little pieces may shred off inside the line and clog up your orifices and appliance valves. The gas stuff is tougher/heavier and less likely to do that. I'll use it in a pinch but I do like the liquid stuff better.

 

[jrkettle]

I just ran a new gas line out the back of my house for my brew stand. I used pipe dope everywhere, I used gas tape at first, but found the pipe dope to be easier and faster.

One thing I had problems with was alignment of elbows, tees and ball valves. I found that if I left about a quarter to a half turn on the pipe before the elbow or tee, it gave me a little extra adjustment to get the tee or elbow in the right spot.

 

[BucksPA]

I just ran a new gas line out the back of my house for my brew stand. I used pipe dope everywhere, I used gas tape at first, but found the pipe dope to be easier and faster.

One thing I had problems with was alignment of elbows, tees and ball valves. I found that if I left about a quarter to a half turn on the pipe before the elbow or tee, it gave me a little extra adjustment to get the tee or elbow in the right spot.

yeah, i'll get the pipe dope..its cheap and will work better im sure. i was already battling the alignment when putting it together for a quick test.

 

[Fletch]

Also, you mentioned unions, but not coulplings. I'm guessing what you were calling a union is actually a coupling. Unions are not allowed on gas piping, EXCEPT at the meter and an actual appliance, and must be left exposed.

 

[Bobby_M]

Um, is 3 x 120kBTU burners on a jury rigged stove allowed? What's a couple extra unions?

 

[wilserbrewer]

.... have some pipe wrenches and plan on tightening the pipes and fittings with great force. ..

Agreed w/ the pipe dope, but it really should not take great force, just nice and firm should get the job done.

 

[Pops]

Ive done three NG projects in my home, garage heater, NG BBQ, and basement brewery, all three pipe dope. That being said, google, and read up, your local codes might specify tape or dope. I read you can use both, I don't know, its your house, research, and good luck.

 

[GNBrews]

Agreed w/ the pipe dope, but it really should not take great force, just nice and firm should get the job done.

+1 Over-tightening is the number one cause of leaky pipe threads.

 

[Marsdude]

I have always used Rector Seal and it has worked well.

http://www.rectorseal.com/index.php?site_id=1&product_id=212

You can get it a HD. Ditto on not tightening too much. Also ditto on using the dish soap solution to check for leaks. I mix some in a spray bottle and spray it on joints when under pressure and look for bubbles.

 

[BigJason]

i got the gas rated teflon tape, have some pipe wrenches and plan on tightening the pipes and fittings with great force. other then searching for leaks after everything is tightened, can you think of anything else?

Agree with the others, use Pipe Dope, and do NOT use "Great force". One thing to keep in mind is that black pipe fittings are a tapered thread. This means that as you thread the pipe into a fitting, the threads get larger in diameter. I've seen guys break off pipe by cranking way to hard on the end of a monkey wrench.

Another thing, if you have over tightened a fitting and need to back it off, I was taught that you're better off taking it all the way back out and reappling pipe dope. I'm talking about fitting an elbow or tee at a specific angle... if you need to turn it back, you're better off redoing it.

 

[DevilsCreekBrewing]

I am in school right now to be a Gas Tech, so I've been doing quite a bit with black pipe lately. We use the pipe dope on every thread, and if the threads are suspect, we use the teflon tape as well. What I was told to do with the tape if using it, is to not run it within 1/8 of the start of the thread. It can't get any into the line that way I suppose.

 

[jaginger]

Um, is 3 x 120kBTU burners on a jury rigged stove allowed? What's a couple extra unions?

LOL, this struck me pretty funny when I read it. Or maybe i just need to go to bed.

:fro:

 

[BucksPA]

Also, you mentioned unions, but not coulplings. I'm guessing what you were calling a union is actually a coupling. Unions are not allowed on gas piping, EXCEPT at the meter and an actual appliance, and must be left exposed.

you're right, i was referring to couplings. I have one union, and it's a 1/2" to 3/8" union flare that goes to my regulator. i appreciate all the valuable feedback. heading to HD now for some pipe dope. I will not use "great force." when tightening. I must have been thinking about star wars when i was writing that. I was under the assumption that tighter is always better, but you proved me to think otherwise.

thanks.

 

[jrkettle]

I found that going hand tight, then giving about another turn maybe two with the wrench was enough and still allowed some room to adjust for tees and elbows.

 

[Bobby_M]

LOL, this struck me pretty funny when I read it. Or maybe i just need to go to bed.

:fro:

Behind the joke was sort of the point that while the hard piping tied in to the rest of the house's system absolutely needs to be to code, once you get to the rig itself, you can relax a little. This part of the system, if you planned well, will NOT be pressurized indefinitely.

 

[Great_Neck_Brewer]

I'm a plumber by trade

1.) Don't over tighten your connections. Your only holding back 6 psi at most which you could hold back with your thumb. You should make a firm connection where you could still tighten it if you had to.

2.) Use the yellow gas rated tape. People use the pipe dope, put too much on and clog the lines and connection. Tape is aslo cleaner.

3.) Use leak check. Don't make your own if this is your first time with gas lines. You want to make sure it is the right mixture.

 

[HBHoss]

Just had my hard line hooked up today and the propane guy uses both tape and dope. He left me a used can of dope so I could secure my connections. No leaks.

 

[Fletch]

you're right, i was referring to couplings. I have one union, and it's a 1/2" to 3/8" union flare that goes to my regulator.

Bucks, is this piping NG or LPG (Propane)? The mention of a 1/2" to 3/8" fitting makes me think propane. If so, you don't have a whole lot to worry about, other than making all of your connections gas-tight.

IF it's NG, you also have to be careful not to exceed the capacity of the line you're connecting to. I occasionally see posts by brewers who want to connect their NG burner-equiped brew rig to an existing pipe to a furnace, water heater, etc. Doing that can easily exceed the capacity of the existing pipe, which can be dangerous. If the gas pressure drops too low, it will result in incomplete combustion in the existing appliance, generating Carbon Monoxide.

 

[DevilsCreekBrewing]

Bucks, is this piping NG or LPG (Propane)? The mention of a 1/2" to 3/8" fitting makes me think propane. If so, you don't have a whole lot to worry about, other than making all of your connections gas-tight.

IF it's NG, you also have to be careful not to exceed the capacity of the line you're connecting to. I occasionally see posts by brewers who want to connect their NG burner-equiped brew rig to an existing pipe to a furnace, water heater, etc. Doing that can easily exceed the capacity of the existing pipe, which can be dangerous. If the gas pressure drops too low, it will result in incomplete combustion in the existing appliance, generating Carbon Monoxide.

Adding pressure draw to a system not rated for that draw in BTUH won't cause incomplete combustion. Incomplete combustion is caused by a reduced oxygen level in the combustion chamber. So you end up with CO + H2O instead of CO2 + H2O as the combustion products.

You will have poor efficiency on the appliances in the system if you are trying to draw more fuel than can be supplied. More frequent on/ off cycling, extended run times in some cases etc.

 

[Marsdude]

I'm a plumber by trade

1.) Don't over tighten your connections. Your only holding back 6 psi at most which you could hold back with your thumb. You should make a firm connection where you could still tighten it if you had to.

2.) Use the yellow gas rated tape. People use the pipe dope, put too much on and clog the lines and connection. Tape is aslo cleaner.

3.) Use leak check. Don't make your own if this is your first time with gas lines. You want to make sure it is the right mixture.

Good advice. Although I have always used dope with gas, I will try the tape next time.

 

[BucksPA]

Bucks, is this piping NG or LPG (Propane)? The mention of a 1/2" to 3/8" fitting makes me think propane. If so, you don't have a whole lot to worry about, other than making all of your connections gas-tight.

IF it's NG, you also have to be careful not to exceed the capacity of the line you're connecting to. I occasionally see posts by brewers who want to connect their NG burner-equiped brew rig to an existing pipe to a furnace, water heater, etc. Doing that can easily exceed the capacity of the existing pipe, which can be dangerous. If the gas pressure drops too low, it will result in incomplete combustion in the existing appliance, generating Carbon Monoxide.

it is propane. the first time i hand tightened the connections, I had some flare-ups at some connections, so then i tightened em up with a wrench and it seems to better. No incidence of any leaks, but I don't know for sure without using dish soap or some gas leak check. I'm going to just buy a gas leak solution and use that. thanks.

 

[Fletch]

Adding pressure draw to a system not rated for that draw in BTUH won't cause incomplete combustion. Incomplete combustion is caused by a reduced oxygen level in the combustion chamber. So you end up with CO + H2O instead of CO2 + H2O as the combustion products.

You will have poor efficiency on the appliances in the system if you are trying to draw more fuel than can be supplied. More frequent on/ off cycling, extended run times in some cases etc.

That's only part of the equation. You left out C. C for simple Carbon, in the form of soot. Atmospheric burners* are dependent on the velocity of the fuel gas through a venturi to draw in primary combustion air. As the gas supply pressure drops, so does the velocity. Less air is drawn in, and this DOES result in incomplete combustion, as clearly evidenced by soot formation. Turn the pressure down on just about any burner, propane or NG, and you'll see what I mean.

It's one thing to soot up your brew kettle, it'll just cost you longer brew time and extra gas consumed, plus more time to clean it up. With a brew rig fed by a separate propane source, no big deal. But if your rig is connected to a household gas system, sooting up your fixed furnace and/or water heater CAN AND WILL lead to the generation of excessive amounts of Carbon Monoxide. This is why gas appliances come with documentation stating the minimum required gas pressure. Some newer furnaces and most commercial gas appliances have low pressure safeties for this reason. It's also the reason that Mechanical Codes have fuel gas pipe size requirements.

*A burner that does not have air supplied a blower. In other words, all homebrew rig burners, 99% of water heaters, and most older furnaces

 

[DevilsCreekBrewing]

That's only part of the equation. You left out C. C for simple Carbon, in the form of soot. Atmospheric burners* are dependent on the velocity of the fuel gas through a venturi to draw in primary combustion air. As the gas supply pressure drops, so does the velocity. Less air is drawn in, and this DOES result in incomplete combustion, as clearly evidenced by soot formation. Turn the pressure down on just about any burner, propane or NG, and you'll see what I mean.

The formula for complete combustion of methane is CH4 + 2O2 -> CO2 + 2H2O

The formula for incomplete combustion of methane is 2 CH4 + 3 O2 -> 4 H2O + 2 CO

No forgotten C there.

It's one thing to soot up your brew kettle, it'll just cost you longer brew time and extra gas consumed, plus more time to clean it up. With a brew rig fed by a separate propane source, no big deal. But if your rig is connected to a household gas system, sooting up your fixed furnace and/or water heater CAN AND WILL lead to the generation of excessive amounts of Carbon Monoxide. This is why gas appliances come with documentation stating the minimum required gas pressure. Some newer furnaces and most commercial gas appliances have low pressure safeties for this reason. It's also the reason that Mechanical Codes have fuel gas pipe size requirements.

*A burner that does not have air supplied a blower. In other words, all homebrew rig burners, 99% of water heaters, and most older furnaces

I agree that if soot is being generated, excessive amounts of CO are being generated. That was not included at all in the first post I quoted.

Sooty flames are typically generated by a rich fuel level and no premixed oxygen, a diffusion flame.

Atmospheric burners use the pressure of the fuel to entrain the primary air, but this primary air doesn't not have a low restriction that correlates to a flow restriction in fuel. The amount of primary air required is going to differ by design, with secondary air making up the balance.

All of my information has been taken from the George Brown and Fanshawe College manuals for Gas Tech III and II, as well as from the CAN/CSA-B149.1-05 Natural Gas and Propane Installation Code.

 

[jlmcgrath]

My dad always says, tight is tight, to tight is broke.

 

[dmfa200]

Never over tighten threaded fittings.

Here is a reference on thread engagement by hand, and the effective thread(using a wrench)

http://www.sizes.com/materls/pipeThrd.htm

Built and installed natural gas steam boilers for a while, years ago.

 

[lebshiff21]

it is propane. the first time i hand tightened the connections, I had some flare-ups at some connections, so then i tightened em up with a wrench and it seems to better. No incidence of any leaks, but I don't know for sure without using dish soap or some gas leak check. I'm going to just buy a gas leak solution and use that. thanks.

Make sure you get the pipe dope rated for propane. There's a few different kinds at HD. The propane rated stuff is like $7-8/jar.