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Brad Sperr
04-30-2008, 12:50 PM
I'm interested in getting advice from any pros or diy'ers who have experience extending natural gas lines. I have an existing line in my home that I'd like to extend for a new gas range and fireplace. I'll be getting some estimates on the job, but, with the way the appliances are situated, I think it's going to be pretty pricey. Being a new homeowner with very little money for improvements, I'd like to take a crack at it myself in that event.

The existing line is just the standard black iron in a well-ventilated crawl space, and there's a short section along one wall with a plug on the end that looks like it was meant for future expansion. From there, it's a straight shot (~20ft) to the fireplace and you would have to tee off somewhere in the middle of that run (~15ft) for the range.

If I were to do this myself, I was thinking that I could measure off the runs, and have the Borg cut and thread all of the pipe I need. I know how to cut the gas off at the meter, cut off pilot lights, bleed the lines, and I know basically how to dope and tighten NPT fittings. Aside from adding drip legs at the valve connections at the appliances, I don't know what more you would need to do. As far as checking for leaks after re-pressurizing the system, it seems like a lot of people use soapy water.

Does anyone have any general advice/encouragement in this area or recommend any resources to look at? I'm aware that natural gas can be very dangerous, but so is electricity, and there are plenty of diy threads about that. If I did it myself, I would want to learn as much as possible so that I could comply with all applicable codes. I would also do it under permit and have it inspected, which is permissible in my area. Thanks.

Ken Fitzgerald
04-30-2008, 12:59 PM
Good luck!

When I was a child we had a home burn down due to a natural gas leak. My mother and father never did completely recover from the economic loss as they didn't have insurance. Thank God we were away for the evening when it happened. A truck driver driving by on US 50 kicked in the door to make sure nobody was in the house. His statement helped locate the initial location of the fire.

I work with 3-phase electrical daily.....upto 160 KV DC daily......cryogenic liquids (Lhe) regularly....supercon magnetic fields upto 3.0 T daily.....eletrical mechanical frames upto 3,000 lbs spinning continuously at 1 revolution in 0.35 seconds.

I won't do NG. I pay the pros....I sleep better!

JMHO

JohnT Fitzgerald
04-30-2008, 1:04 PM
I've done some 'minor' NG pipe work before (if any of it can be called 'minor'). Sounds like you have all the steps down, but the one thing that pops to mind for a fireplace is whether or not the exiisting meter and pipes have sufficient capacity for the addition of a fireplace.

Use soapy water to check for leaks. I've also gone back a few times afterwards (later in the day and the next day) to check for leaks. Thankfully, NG has a stink added to it so you'd be able to detect it pretty quickly.

Cliff Rohrabacher
04-30-2008, 1:12 PM
I put my own gas line in. I used 1" black iron 'cause the threader rental didn't go any smaller.

Every time you transition from horizontal to vertical install a T and run a capped down tube no less than 6" long to catch sediment.

I like Harvyseal. But I'm sure most of the pipe dopes are good.

Test for leaks:
Use a compressor (a manual bike pump will do) and an inner tube filling fitting and a good pressure gauge. You can get it all from the plumbing supply. They'll know exactly what you are doing.
Pressurize the line and make a note of the pressure. I like a hundred pounds for black iron ( 20 PSI for thin copper pipe).
Come back in a day or two and see if it's dropped. If it has, get a bottle of children's bubble soap (or any bubbly soap), re-pressurize the system and go from one end to the other brushing the soap on the joints looking for leaks.

Most leaks are in the joints. If you have a leak and it's not in the joints, test that Pressure gauge head you installed to test pressure. Then if the pressure gauge assy' isn't leaking , test the cast iron fittings themselves. If they don't lead test the pipes. I have never seen or heard of a pipe leaking but hey.

IF no leaks are discovered but the line pressure dropped you either didn't test very well or you ran out of pressure before you got to the leak. You'll need to keep pressure on the system while testing.

Over tightening the plumbing cast iron fittings can crack 'em. Ya want 'em nice and tight but, not Herculean tight The pipe dope is what's giving you the seal not the tightness of the threaded pipe connection. That's why you should never cheap out on pipe dope.

David G Baker
04-30-2008, 4:05 PM
I have been working on NG lines since I was in my late teens and they aren't any more problematic than water lines to install if you have minor pipe fitting skills. I use Cliff's method of testing the lines for leaks, air pressure and a pressure gage or soap applied with a paint brush and look for bubbles. I use a pipe dope specifically designed for gas pipes on all fittings and I try to stay away from pipe unions if possible.
The Borgs now sell a flexible gas line in rolls that I have never tried but may work for you as well.

Chris Padilla
04-30-2008, 4:25 PM
One concern I have is to make sure you have enough gas to satisfy the two appliances. What size is the pipe? Is it large enough?

Dig deep into what the inspectors will want. They could make you run a brand new line directly from the meter! If you get some estimates, be sure to pick their brains as well and make sure they know this will be a permitted job.

I've had fairly minor gas line done at my house and I always overpaid someone to do it for me! ;) Water, electricity, drywall, framing, concrete...no problem...NG....problem! :D

Brad Sperr
04-30-2008, 5:15 PM
One concern I have is to make sure you have enough gas to satisfy the two appliances. What size is the pipe? Is it large enough?

Dig deep into what the inspectors will want. They could make you run a brand new line directly from the meter! If you get some estimates, be sure to pick their brains as well and make sure they know this will be a permitted job.

I've had fairly minor gas line done at my house and I always overpaid someone to do it for me! ;) Water, electricity, drywall, framing, concrete...no problem...NG....problem! :D

I'm not sure what the demand of the two appliances would be, but I imagine they would be pretty high. I'll ask the plumber what he thinks about whether my current pipes can handle it when he comes out tomorrow.

I'm also brainstorming about how to connect the gas logs because I'm converting a traditional masonry fireplace. The gas log burner pan has a brass flared inlet. The pan also has two valves to control the gas flow. I'm thinking that I can fish some flexible copper tubing through the wall of the fireplace and through the adjoining stud wall and down to the crawl space to join with another cut off valve on the black iron. If I protect the tubing from puncture behind the stud wall, can anyone think of a problem with this approach? There wouldn't be any unions behind the wall.

Mike Henderson
04-30-2008, 5:37 PM
I've done gas lines and the hardest thing is to get the pipes the right length. You have to learn how much to allow for each joint. It's not like copper where you can just "cut to fit".

But even if you have to run to the Borg a few extra times and pay for some additional pipe, you'll come out cheaper. Just do a good job and follow the suggestions given earlier. Cliff has some very good advice.

Everybody who does gas lines, even a plumber, had to do their first gas line sometime.

Mike

Randy Cohen
04-30-2008, 5:43 PM
its been a while but i've done natural gas lines myself without any trouble. do the soapy water check as others suggest. take your time and get your stuff at the plumbing supply place...they will help you especially with the pipe lengths and any code requirements. the number of gas appliances hooked up doesn't make much difference unless they are all being used at the same time. get a book on the subject and read it a couple of times.

Jim Becker
04-30-2008, 7:51 PM
Brad, I recommend you still have a pro do it, even if you "can" do the work. It's not just the installation work that has to be taken care of, but you also need to insure that everything is sized correctly for the new points of gas usage including your meter. I just went through this for our addition. PECO (our local electric and gas utility) had to change out our meter and to handle the flow requirements, the branch to the addition had to come right off that meter as the service into the original structure was not large enough. It all has to be engineered properly. It's doubtful that adding a fireplace and range is going to material affect things, but you do need to be sure. (The new meter and it's installation was free, but the run from that point to the addition was the responsibility of me/my HVAC sub and cost some money)

Christopher Stahl
04-30-2008, 9:15 PM
I run all new piping for LP in our house. Our house is relatively new, but the propane was for the fireplace only. After we moved, I extended the line for the dryer and just last fall I run all new lines completely because we converted our cooktop to gas and connected the outdoor grill to the gas line. I also added additional connections for both of our water heaters as I plan to change them to gas in the near future.

On top of what was already said, make sure to do some calculations for the amount of gas that each device requires. You simply just don't want drop in some lines. I will say it was not fun as I had to run some longer lines and my hands were sore when I finished. Black iron is dirt cheap, so I saved quite a bit running them myself.

Just be careful not to crack any of the black iron or brass fittings if you use them by over tightening.

I had the our gas utility come in and test when I was finished. I felt it was the safest thing to do and they didn't charge me anything for the test since I was adding a couple appliances to the service. They're always happy to take more of your money. :-)

Al Willits
04-30-2008, 10:01 PM
I'vew worked in the feld for almost thiry years and all I'll say is have some one do it.

Nothing like standing next the the frie chef while watching a house burn down because someone wanted to save a few bucks.

Plus if permits are required you'll need to know codes, also the're are charts for running gas line and if there's not enough gas line you run into more problems, some can be fatal.

While some may think its the same as running water lines, I'll assure you its not, water leaks are annoying, not always so with gas and if your garden hose doesn't get enough water, no big deal, gas burning devices need the proper pressure to stay safe.

Al