Gas line repair (I hope...)

25 some years ago I buried a 1/2" copper pipe from the house to the shop, and used it as a natural gas line for many many years. (Don't worry - only compression fittings above ground, but soldered connections underground...) It's about 30' long. A few years ago I smelled a leak outside when I turned it on in the Fall, and confirmed it was leaking with a pressure test (50 psi would drop to nothing within about half an hour). So anyway I've made do with no gas heat in the shop for the past few years.

Last month I successfully repaired the leaky fuel tank in my old Nissan pick up with the Eastwood gas tank repair kit (Google it if curious) and that gave me an idea - let's try the same thing with the old gas line!

I calculated the approx. volume of the line (~2 quarts). Hey - I've got a bit more than half a gallon of waterborne polyurethane varnish left over from re-doing the kitchen floor! So I put lengths of clear vinyl tubing on both ends of the line, filled it up with varnish and let it sit for an hour. I then drained and blew out the excess with compressed air. I figure I need to keep blowing air through it for 24 hours or so, so I fabricated this high-tech device to do that:



There is a computer fan in the cardboard thing, and it's putting a nice little breeze through the line into the basement.

I'll do another coat tomorrow, then dry it for several days, then pressure test it again. Wish me luck ;D

Kind of like what the new coated lines are made like.

Kenny

Perhaps someone with more knowledge than I would advise but is there a chemical reaction between polyurethane and gas. ???

Best Regards
Bob

While digging up the existing failed line and replacing it with new stuff is a big pain and copper is really expensive, it seems a fair trade-off against the possibility of blowing up your house or your shop or both from a gas leak. Were that to happen the insurance company might take a dim view of this type of repair. You might get lucky and find that some of the newer yellow gas line will fit through the existing line and you could push the new stuff through. I don't even know if "civilians" can buy that stuff or if you have to be licensed to buy it or if the resulting smaller size would support the heater in your shop. Good luck with whatever path you decide on.

I would hope that better judgement will prevail here. There are reasons why copper is not used for buried gas line installations, other than the cost. It would serve you better to bite the bullet and do the excavation and install the proper pipe for your furnace. It's only 30', or about three lengths of pipe. The fix that you are attempting here sounds like a band-aid on a heart attack. That resin is not formulated for the extreme conditions that it will be subjected to and will most likely fail in short order, more than likely in the most inopportune time, read middle of winter. Do the heavy lifting now while the weather is still tolerable, if not dry.

BC1
Jim

I am usually one to take short cuts and look at regulations and building codes etc with an eye to how reasonable they are but playing with natural gas scares me. The potential of a silent accumulation of a large quantity of explosive gas leading to a workshop where sparks are intentionally produced? Doesn't seem like a good idea.

Think about it this way. In 25 years the copper pipe has been corroded enough in at least 1 place to let the gas out. What are the odds that 1 place is the only place, that the corrosion won't continue, that your leaking gas detector (you) picks up on the problem before its a disaster (ie you are home to detect the problem), and your repair will hold?

Put a new line in (the yellow poly type) and it will outlast you in a much safer way...your neighbors will be grateful!

All of the above.

When I first read this earlier today I thought it all sounded a bit dodgy. I'm surprised the copper pipe, having been buried for 25 years, hadn't already contributed to putting the shed into orbit.

Pete

The installation met code originally, except for the soldered joints underground. I worked in the building trades and ran the plan by an architect before putting it in A quick perusal of the current Ohio code this morning seems like it still does.

However I am a bit concerned about the possibility of corrosion in the pipe itself. Apparently 25 years is a good long time for any underground pipe installation... I may dig up the short portion that's not under concrete and have a look at it.

I don't know about the Ohio code, but in Ontario you have to be a licenced Gas fitter to do any gas work more complicated than relighting a pilot. The 1/2 pipe may meet the code, but I would like to see where repairing it like you describe meets code.
Regards,
Gerald.

Did a pressure test this afternoon on the single coat of stuff - it was still leaking. I've now got it filled up again, but this time I have it under pressure with the varnish in place. It's been holding ~50 psi for an hour or so. Presumably, the varnish has been forced out through the leaking spot(s) and it is viscous enough to seal against that pressure. Makes me think the leak is a tiny little weep in one of the soldered joints...

I'm going to leave it under pressure like this till Monday, then drain / blow it out, dry it for several days and test again.

I appreciate everyone's concerns for my safety, but want to point a few things out. First of all, the line in question is entirely outside - not inside. If it leaks, it's not going to be filling up any enclosed space, but only venting to the great outdoors (and running up my gas bill). I've got a super-sensitive nose for gas perfume, so I'll notice it. Second, I'm not going to be satisfied with it until it can hold 50 psi for a day. That's about 25 times more pressure than the approx. 2 psi working pressure in the system here. Pretty good safety factor if you ask me...

Copper pipe meets code for direct burial gas lines, and this particular one has worked fine for decades. Thanks for the concern, but I have no intention of blowing anything up

Dave....for the record. on behalf of HMEM...get a professional to come out and go through that line and find out what's going on......

Some things aren't worth messing with....gas is one.

Go modern....go gas! go boom!............. 8)

Dave

For my money, the repair has all the hallmarks of a desire to become a temporary American. Gas is something that you don't muck about with. If it has corroded in one place it will most certainly be corroded somewhere else.
The choice I know is yours. I do suspect however, that given the twitchy litigation system in the US you wouldn't have a leg to stand on if a leak caused injury or illness or an ignition caused damage.
For my money, do it once, do it well, and do it properly.
Steamboat Willie.
PS it will be too far for me to attend any Rememberance Service.

Kludge fixes of something as potentially dangerous as natural gas is not to be contemplated. The only safe option is replacement.
Hoping you do the right thing
Ernie J

Hi

If I rember correctly Dave (dgjessing) made a post on the old site about having tries to fix it a 2nd time. It would not hold pressure when he tested it so he said that he was going to dig it up and install new gas line as well as cable and either phone or water. He said he was going for the whole package anyway.

I hope this will ease your minds of some of your concerns. I don't think Dave wants to creat any potential danger zones.

Cheers (smile)

Don

dsquire said:

Hi

If I rember correctly Dave (dgjessing) made a post on the old site about having tries to fix it a 2nd time. It would not hold pressure when he tested it so he said that he was going to dig it up and install new gas line as well as cable and either phone or water. He said he was going for the whole package anyway.

I hope this will ease your minds of some of your concerns. I don't think Dave wants to creat any potential danger zones.

Cheers (smile)

Don

Click to expand...

Yep - and I was just now going to add that back in to this thread (but you beat me to it!). I'm collecting materials and planning the trench digging party - all the beer you can drink as long as you take a turn with a shovel

dgjessing said:

Yep - and I was just now going to add that back in to this thread (but you beat me to it!). I'm collecting materials and planning the trench digging party - all the beer you can drink as long as you take a turn with a shovel

Click to expand...

Dave

I would be glad to come and help you. Only problem is I would have to stop with just drinking the beer. Since I am on oxygen picking up a shovel and putting it to work would do me in. I'm OK with the beer as long as I use the regular bottles and not the quarts (Canadian size) and don't get in to much of a hurry. HAha. I can still supervise pretty good though.

Hope all goes well.

Cheers (smile)

Don

Save yourself some beer money!

Ditch Witch:


Local equipment rental places have them.
One buddy to run the Ditch Witch, another friend to help the first lay the
pipe, then the two of them can push the dirt back into the trench.

You just pay the Ditch Witch rental and keep the beer cold!

Rick

Dave
Just take care, we need more members not less..........
Sorry just couldn't help myself.
Kindest Regards
Beagles

Well today was trench party day! One person showed up But most of the difficult stuff is done, including tunneling under the sidewalk. I can finish up myself tomorrow. Can't believe how much rubble there is buried in my yard - hunks of concrete, broken bricks, all kinda crap.