Capping a gas line?

[Hank11]

I'm removing a gas water heater. I have iron pipe coming through a wall with a cut off valve in line, another foot of iron pipe, then a connection to a flex hose then to the heater. Can I leave the cut off valve in the line then cap the pipe, test for leaks and just leave it?

I will end up with the iron pipe coming through a wall, a cut off valve, a little more iron pipe, then an iron pipe cap in that order.

Thanks.

 

[mike93lx]

Leaving the valve to make a future hookup easier? Personally, I'd remove the valve and cap it closer to the wall to get it all out of the way.

 

[BillK]

Or just put a plug in the end of the valve and be done with it.

 

[NUTTSGT]

When you say "cut off valve" you mean a shut off valve and not something that has been cut on, correct ?


I'd leave the ****** coming out of the valve and put a cap on it with the correct pipe dope. Unless it's in the way, I see no reason to remove it if it doesn't currently leak.

I would also prefer not to put a plug in the end of the valve either. I'd rather leave a valve alone, once installed rather than taking a chance of breaking, cracking or rounding the edges off it it trying to tighten or loosen something attached to it.

 

[manwithtools]

When you say "cut off valve" you mean a shut off valve and not something that has been cut on, correct ?

Welcome to the South Eric. Anything that can control the flow of water, gas, electricity, etc. is called a "cut-off" or "cut-on". It's common for folks here to say "Cut on the lights please". Cracks me up every time I hear it. By definition, cut is to disconnect, but that does not matter here.

What's even better is the "cut-off" valve for water outside is commonly connected to a "hose-pipe"

In this instance, "cut-off" means "shut-off" valve.

 

[Jim greengo]

I'm removing a gas water heater. I have iron pipe coming through a wall with a cut off valve in line, another foot of iron pipe, then a connection to a flex hose then to the heater. Can I leave the cut off valve in the line then cap the pipe, test for leaks and just leave it?

I will end up with the iron pipe coming through a wall, a cut off valve, a little more iron pipe, then an iron pipe cap in that order.

Thanks.

Yes

 

[NUTTSGT]

Welcome to the South Eric. Anything that can control the flow of water, gas, electricity, etc. is called a "cut-off" or "cut-on". It's common for folks here to say "Cut on the lights please". Cracks me up every time I hear it. By definition, cut is to disconnect, but that does not matter here.

What's even better is the "cut-off" valve for water outside is commonly connected to a "hose-pipe"

In this instance, "cut-off" means "shut-off" valve.

I assumed as much, just wanted to make sure. In my line of work, I have seen some "stuff" and wondered why has this place not burned down yet. We won't even go into the way some people around here talk or the way their brains work.



Ever seen a Gas Meter spark ?

 

[manwithtools]

Ever seen a Gas Meter spark ?

Can't say that I have, but not much surprises me anymore.

 

[CraigStu]

Are you installing an electric water in approximately the same location? Would it shield all the piping and valve at least somewhat from getting bumped into? I am having a little trouble understanding how far from the wall the pipe and valve and pipe will be.

 

[PoorUB]

You can put in a short ****** and cap to plug the valve, or remove the valve and cap it closer to the wall if you like.

I would advise not leaving the gas on and plugging it with your finger while getting the cap ready to install. One slip up and you have a basement full of natural gas!

I worked with gas for many years and I have piped live gas, but only outside. I would never do it inside!

 

[rooster59]

I would just add to make sure your sealer is spec-ed to be good for propane or NG.

 

[PCustoms]

You can put in a short ****** and cap to plug the valve, or remove the valve and cap it closer to the wall if you like.

I would advise not leaving the gas on and plugging it with your finger while getting the cap ready to install. One slip up and you have a basement full of natural gas!

I worked with gas for many years and I have piped live gas, but only outside. I would never do it inside!

One slip up....for several hours. You sound scared of gas....



I feel like this is one of those simple jobs that if you have to ask, you shouldn't be doing it.

 

[mike93lx]

You can put in a short ****** and cap to plug the valve, or remove the valve and cap it closer to the wall if you like.

I would advise not leaving the gas on and plugging it with your finger while getting the cap ready to install. One slip up and you have a basement full of natural gas!

I worked with gas for many years and I have piped live gas, but only outside. I would never do it inside!

Full of gas? Wow

 

[fritz29]

You can put in a short ****** and cap to plug the valve, or remove the valve and cap it closer to the wall if you like.

I would advise not leaving the gas on and plugging it with your finger while getting the cap ready to install. One slip up and you have a basement full of natural gas!

I worked with gas for many years and I have piped live gas, but only outside. I would never do it inside!

You could also remove the ****** and replace with a male pipe plug

 

[PoorUB]

One slip up....for several hours. You sound scared of gas....



I feel like this is one of those simple jobs that if you have to ask, you shouldn't be doing it.

Full of gas? Wow

No, but I like to play it safe and never would recommend to someone I don't know to deal with live gas in an enclosed space.
I am certain I can do it, but I am not certain the next guy can.

"I feel like this is one of those simple jobs that if you have to ask, you shouldn't be doing it."

Exactly! I am assuming the OP is not knowledgeable about gas and gas fittings, or he would not have asked the question. There for I would not recommend he work on live gas.

We have a large range of people on this group. Some guys could build about anything, some guys are worthless with tools. There is a large gray area in between.

Pus, consider if he tries to unscrew the pipe ****** and it breaks of. Now he has no way of shutting off the gas other than sitting there with his finger in the hole like the little dutch boy. Say he says screw it and runs outside to shut of the meter and the valve will not turn with the 12" pipe wrench he has. Now what does he do? Plus we don't know if he is dealing with 1/2 PSI or 2 PSI. It can be a a lot of gas in an enclosed area in a short time. Maybe there is a furnace with a standing pilot, five feet away from where the water heater was. Have you ever lit up a 1/2" black pipe with free flowing gas? I have seen it happen, and wouldn't like to see it in my house.

How much time of 1/2 PSI, or worse, 2 PSI in an enclosed space does it take before it becomes a serious situation?

As for the valve at the meter being stuck, I have seen it a few times. A 24" pipe wrench just broke off the valve stem on one I remember.

And for the record, I have done a lot of gas piping. I had to remove a 2" ball valve and replace it as it would not close 100%, plus we could not shut down the gas in the building. I closed the valve as best I could, removed the pipe up to the valve. Unscrewed the old valve, held my hand over the end, smeared some Rectorseal on the pipe threads and screwed on he new valve. I was outside and it was a windy day. I surely would no recommend it to a rookie.

 

[Hank11]

When you say "cut off valve" you mean a shut off valve and not something that has been cut on, correct ?


I'd leave the ****** coming out of the valve and put a cap on it with the correct pipe dope. Unless it's in the way, I see no reason to remove it if it doesn't currently leak.

I would also prefer not to put a plug in the end of the valve either. I'd rather leave a valve alone, once installed rather than taking a chance of breaking, cracking or rounding the edges off it it trying to tighten or loosen something attached to it.

Yes, shut off valve.

Welcome to the South Eric. Anything that can control the flow of water, gas, electricity, etc. is called a "cut-off" or "cut-on". It's common for folks here to say "Cut on the lights please". Cracks me up every time I hear it. By definition, cut is to disconnect, but that does not matter here.

What's even better is the "cut-off" valve for water outside is commonly connected to a "hose-pipe"

In this instance, "cut-off" means "shut-off" valve.

Here, let me help you yankees — I’m putting in a hot water heater and I did use my hosepipe to drain the old one. Hooked it right to the cut off valve on the drain. Ain’t nothing like hot water and a warshrag to clean up with.

 

[48windsor]

Welcome to the South Eric. Anything that can control the flow of water, gas, electricity, etc. is called a "cut-off" or "cut-on". It's common for folks here to say "Cut on the lights please". Cracks me up every time I hear it. By definition, cut is to disconnect, but that does not matter here.

What's even better is the "cut-off" valve for water outside is commonly connected to a "hose-pipe"

In this instance, "cut-off" means "shut-off" valve.

thats funny

 

[Death Row Dave]

I worked 36 years in the gas / liquid pipeline industry . YES I have “ flew on hot “ many gas and liquid fittings without cutting off the flow . The pressures inside one’s home are very low and controllable . Would I suggest to someone untrained to do it NO. Use the CUT OFF valve to shut off the flow , remove the flex hose and adapter to attach it from the black iron pipe and plug or cap , leaving the CUT OFF closed .

Funny thing my wife was raised in the Deep South so cut it on and cut it off , is something I experienced many years ago with a WTH does that mean ? Her response “ nothing to a **** Azz like you . “

 

[NUTTSGT]

No, but I like to play it safe and never would recommend to someone I don't know to deal with live gas in an enclosed space.
I am certain I can do it, but I am not certain the next guy can.

"I feel like this is one of those simple jobs that if you have to ask, you shouldn't be doing it."

Exactly! I am assuming the OP is not knowledgeable about gas and gas fittings, or he would not have asked the question. There for I would not recommend he work on live gas.

We have a large range of people on this group. Some guys could build about anything, some guys are worthless with tools. There is a large gray area in between.

Pus, consider if he tries to unscrew the pipe ****** and it breaks of. Now he has no way of shutting off the gas other than sitting there with his finger in the hole like the little dutch boy. Say he says screw it and runs outside to shut of the meter and the valve will not turn with the 12" pipe wrench he has. Now what does he do? Plus we don't know if he is dealing with 1/2 PSI or 2 PSI. It can be a a lot of gas in an enclosed area in a short time. Maybe there is a furnace with a standing pilot, five feet away from where the water heater was. Have you ever lit up a 1/2" black pipe with free flowing gas? I have seen it happen, and wouldn't like to see it in my house.

How much time of 1/2 PSI, or worse, 2 PSI in an enclosed space does it take before it becomes a serious situation?

As for the valve at the meter being stuck, I have seen it a few times. A 24" pipe wrench just broke off the valve stem on one I remember.

This is a post of experience right here.

 

[Hank11]

I worked 36 years in the gas / liquid pipeline industry . YES I have “ flew on hot “ many gas and liquid fittings without cutting off the flow . The pressures inside one’s home are very low and controllable . Would I suggest to someone untrained to do it NO. Use the CUT OFF valve to shut off the flow , remove the flex hose and adapter to attach it from the black iron pipe and plug or cap , leaving the CUT OFF closed .

Funny thing my wife was raised in the Deep South so cut it on and cut it off , is something I experienced many years ago with a WTH does that mean ? Her response “ nothing to a **** Azz like you . “

That’s what I asked for - a simple straightforward answer. Thank you.

 

[nbpt100]

That’s what I asked for - a simple straightforward answer. Thank you.

I would also add, from someone with experience. Not someone with lots of theory in their head and no experience.

 

[CraigStu]

So for those of you experienced in the industry who say you can swap valves or whatever inside w/o turning off the gas, what do you do about the small amount of gas that inevitably leaks out?

 

[HoosierBuddy]

So for those of you experienced in the industry who say you can swap valves or whatever inside w/o turning off the gas, what do you do about the small amount of gas that inevitably leaks out?

It could be a lot more than a small amount. 10 feet of 1/2" pipe, connected to a sufficient supply of NG at 7" WC, uncapped, would flood the indoor area with roughly 1/4 cubic feet of gas per second. In an enclosed space this could result in an explosive mixture of gas and air very quickly. Then all it takes is one spark.

No one is going to ever tell you it's OK to open a gas line indoors with gas pressure on it.

I do appreciate that the OP is capping this line off. Had a house explosion (fatal) southwest of me a couple of years back caused by this very thing. Replaced the water heater. Left a closed valve UNCAPPED in the home that was no longer being used. Valve got opened somehow. House filled with gas, exploded into kindling killing two occupants, their neighbor, and damaging 39 surrounding homes. No one can say how the gas valve got turned on.

Evansville house explosion that killed 3, damaged nearly 40 homes ruled accidental: investigators

Aerial video posted on social media showed damage in the residential neighborhood with police and fire vehicles on the scene

abc7chicago.com

 

[nicks78camaro]

Shut off gas at meter to be safe

Remove pipe sticking out of the valve and cap it with a short ****** and cap

Or

Remove the valve too and cap off the pipe there

I always use tape then dope on top.

 

[STINEY]

There has been a shutoff valve on every gas meter I have laid eyes on. Crescent wrench, turn off flow at meter, do repair work, turn back on at meter.


Ah shucks....Nick beat me to it while typin.

 

[HoosierBuddy]

Shut off gas at meter to be safe

Remove pipe sticking out of the valve and cap it with a short ****** and cap

Or

Remove the valve too and cap off the pipe there

I always use tape then dope on top.

You'd be surprised to learn that CFR192 requires anyone that turns that valve to be qualified to do so by training and experience with documentation of this maintained by the owner of the valve (the gas company), working within the guidelines of the company's written procedure while doing so, and currently participating in a federal drug and alcohol testing program as per 49 CFR Part 40.

To many, it is not intuitively obvious how to tell if that valve is on or off or which way to turn it. If you break it you're going to have to call the gas company, and possibly 911. And "YES" I have seen where it happened.

I always recommend people put their own shutoff valve in immediately after the meter for this very reason.

PHMSA got involved in this question about 15 years ago and they made it clear that federal OQ rules and D&A rules apply to that valve. Not saying I agree....just saying what your gas company will tell you if you ask about turning that valve.

 

[nicks78camaro]

You'd be surprised to learn that CFR192 requires anyone that turns that valve to be qualified to do so by training and experience by the owner of the valve (the gas company), working within the guidelines of the company's written procedure while doing so, and currently participating in a federal drug and alcohol testing program as per 49 CFR Part 40.

To many, it is not intuitively obvious how to tell if that valve is on or off or which way to turn it. If you break it you're going to have to call the gas company, and possibly 911.

I always recommend people put their own shutoff valve in immediately after the meter for this very reason.

PHMSA got involved in this very question about 15 years ago and they made it clear that federal OQ rules and D&A rules apply to that valve. Not saying I agree....just saying what your gas company will tell you if you ask about turning that valve.

That's surprising but not surprising.

I do agree, if the person can't tell how to close it off then it should be left to a professional.

Hint for OP: when the holes line up on the meter shut off, it's off

 

[Hank11]

It could be a lot more than a small amount. 10 feet of 1/2" pipe, connected to a sufficient supply of NG at 7" WC, uncapped, would flood the indoor area with roughly 1/4 cubic feet of gas per second. In an enclosed space this could result in an explosive mixture of gas and air very quickly. Then all it takes is one spark.

No one is going to ever tell you it's OK to open a gas line indoors with gas pressure on it.

I do appreciate that the OP is capping this line off. Had a house explosion (fatal) southwest of me a couple of years back caused by this very thing. Replaced the water heater. Left a closed valve UNCAPPED in the home that was no longer being used. Valve got opened somehow. House filled with gas, exploded into kindling killing two occupants, their neighbor, and damaging 39 surrounding homes. No one can say how the gas valve got turned on.

Evansville house explosion that killed 3, damaged nearly 40 homes ruled accidental: investigators

Aerial video posted on social media showed damage in the residential neighborhood with police and fire vehicles on the scene

abc7chicago.com

This is why I asked the question.
I know a lot of things but not everything. So, I asked this question because I am not a gas guy, but recognize that gas can be dangerous when done improperly.

 

[nicks78camaro]

This is why I asked the question.
I know a lot of things but not everything. So, I asked this question because I am not a gas guy, but recognize that gas can be dangerous when done improperly.

Do you have other gas appliances in your house like a furnace or range?

 

[Hank11]

That's surprising but not surprising.

I do agree, if the person can't tell how to close it off then it should be left to a professional.

Hint for OP: when the holes line up on the meter shut off, it's off

Propane here, so this does not apply to my case. But its good to talk about.

 

[Hank11]

Do you have other gas appliances in your house like a furnace or range?

Yes, gas cooktop and hvac.

 

[The Cobbler]

the best approach is shut off the gas supply. I would leave the valve and put a cap on , using gas rated dope. don't overtighten the fittings, that is a common mistake for inexperienced people, and it can actually cause a leak by stretching the fittings .
check with soapy water . better yet proper gas leak liquid.
it's not rocket science, but it really should be left to professionals especially if you're not comfortable or knowledgeable in what to do

 

[4x4Pete]

The safe way to deal with this is to call a professional. The second, safest way is to cap the line after the valve and then check for leaks on your cap/fittings with soapy water with the valve turned on.

 

[Crazyjake8493]

Unless the line is in the way, I would always leave a short ****** exiting the shut off valve, and cap off the ******. Makes for an easy future change with a valve right there.

 

[Firebrick43]

Any interruption of service on propane and modifications is to have a "leak check" by a trained individual before putting the system back in service. Soapy water on the joints is not sufficient.

Every state in the nation has adopted some form of NFPA 58 and 54 as code.

NFPA 54 8.2.3 is the original

Tennesse uses the 2012 IRFC which uses the exact same verbiage.

"8.2.3 Leak Check. Immediately after the gas is turned on into a new system or into a system that has been initially restored after an interruption of service, the complete gas piping system and connected appliances or equipment shall be checked for leakage. Where leakage is indicated, the gas supply shall be shut off until the necessary repairs have been made."



The methods for a leak check is in Annex C.3

It must be done with one of the three locations in the system, all using a sensitive calibrated gauge or manometer rated for the psi at the stage of the system where testing and lowered to unlock the regulators.

 

[yatg]

Any interruption of service on propane and modifications is to have a "leak check" by a trained individual before putting the system back in service. Soapy water on the joints is not sufficient.

Every state in the nation has adopted some form of NFPA 58 and 54 as code.

NFPA 54 8.2.3 is the original

Tennesse uses the 2012 IRFC which uses the exact same verbiage.

"8.2.3 Leak Check. Immediately after the gas is turned on into a new system or into a system that has been initially restored after an interruption of service, the complete gas piping system and connected appliances or equipment shall be checked for leakage. Where leakage is indicated, the gas supply shall be shut off until the necessary repairs have been made."



The methods for a leak check is in Annex C.3

It must be done with one of the three locations in the system, all using a sensitive calibrated gauge or manometer rated for the psi at the stage of the system where testing and lowered to unlock the regulators.

yeah, well, the gas company came out a few years ago and changed out the meter.
they didn't leak check anything but their own work, if that.

 

[PoorUB]

Any interruption of service on propane and modifications is to have a "leak check" by a trained individual before putting the system back in service. Soapy water on the joints is not sufficient.

Ha! I don't ever see that happening!

So you shut off the gas to do a minor repair and you have to inspect the whole piping system? Regardless of the size of the system?

 

[Firebrick43]

yeah, well, the gas company came out a few years ago and changed out the meter.
they didn't leak check anything but their own work, if that.

The OP has a propane system, not a NG system, but they should have even still. Did you watch them the entire time? Did they not hook up a gauge at the regulator?

 

[Firebrick43]

Ha! I don't ever see that happening!

It happens every day, its the code.

So you shut off the gas to do a minor repair and you have to inspect the whole piping system? Regardless of the size of the system?

A leak check uses a gauge to check the whole system. Size marginally changes the time it takes to complete the check. It only adds a min or two to bleed off enough pressure to unlock the regulators, for example 9" wc on the second stage regulator from 10.5" wc they are set at.

 

[rsanter]

Leave the valve and put a cap in the end of the valve