Question on Gas Lines

[Tidybuoy]

My summer project is to re-locate my split system A/C & Furnace to the attic as well as install a tankless water heater in the attic. I got a couple of estimates and the cost was shocking and I will have to do some of the work myself, in advance of the actual A/C install. Fortunately, one A/C company gave me a detailed estimate and also told me the code requirements.

Code requires separate, dedicated gas 1" lines to each device and must be "T'd" at the meter. This is something I think I can handle but when I was looking at gas pipes at Home Depot, there are black pipes and also Green coated pipes. I'm wondering what's the difference between these two types of pipe. I hesitate to ask the min-wage employee at Home Depot.

Thanks for any advice

[URY914]

I'm sure your insurance company agrees with you running gas lines on your own. Seems easy enough. Just use some PVC and use the good glue.

[David]

I'm sure someone more qualified than me will chime in but I've always used black pipe for gas. Certainly can't use copper due to chemical reaction.

What do they mean by T'd at the meter? Wouldn't any T's be inside the house? so there's only one line from the meter entering the house?

There are charts for gas flow per pipe size and you should have the BTU's per device so you can calculate the required pipe size.

[javadog]

Regular black iron pipe should not be buried. It's fine for above-ground use. The gas line with the green epoxy coating can be buried, although be careful not to damage the coating on it when installing it.

I've never heard of running separate lines from the meter, but then again, I don't live in the goofy state of California.

[NY65912]

As a NYC Plumber, we run black steel pipe for gas by code.

Gas pipe needs to be tested and inspected.

With all due respect, not a good idea to be doing your own gas piping.

Much loss exposure.

Tee'd at meter,...adding a drip leg at the meter.

[Tidybuoy]

Originally Posted by URY914

I'm sure your insurance company agrees with you running gas lines on your own. Seems easy enough. Just use some PVC and use the good glue.

Thanks for the thoughtful response. I made no mention of using pvc. Just a simple question, what is the difference between Black gas pipe and green coated gas pipe.

I have several friends in the construction business and I will use them for this project. I just don't want to pay the $30,000 estimate that an A/C company gave me which states that customer will supply gas lines to the attic as well as customer will replace all ducts (which may have asbestos). I currently have a raised foundation so access is not an issue. BUT, with any project, I want to educate myself before I pay exorbant prices to any company.

Just fyi, any a/c installer is going to pressure test the lines before installation - it's code.

[Tidybuoy]

Originally Posted by David

What do they mean by T'd at the meter? Wouldn't any T's be inside the house? so there's only one line from the meter entering the house?

There are charts for gas flow per pipe size and you should have the BTU's per device so you can calculate the required pipe size.

The A/C contractor told me that each device (Furnace & Tankless Water Heater) will need seperate dedicated 1" gas lines. He stated that you cannot run a single line and then T between the devices. He also stated that this actually makes it easier for them to pressure test the lines all the way from the meter to the units.

As far as line size, the A/C contractor calculated the needed gas line size based on each unit and the distance to the meter so I am assuming he accurately computed the 1" line. I will do my own calculations to confirm.

[Tidybuoy]

Originally Posted by javadog

Regular black iron pipe should not be buried. It's fine for above-ground use. The gas line with the green epoxy coating can be buried, although be careful not to damage the coating on it when installing it.

I've never heard of running separate lines from the meter, but then again, I don't live in the goofy state of California.

I have a good friend that owns a fire/water restoration business. He has also done a lot of construction work at my plant. He is going to come out and evaluate my situation. He will know exactly what code requirements a required. It's possible that a larger line can be run into the house an then T'd to the individual units but I'm speculating at this point.

[ckelly78z]

Water lines, and electrical are easy, and obvious where the leaks/shorts are, so I end up doing most of this stuff myself. I don't want to be confident enough in my plumbing abilities to try anything with NG...leave that to the certified professionals.

[URY914]

Vern, The PVC was a joke. Hence the green letters.

If by doing it yourself you mean getting someone that is qualified to help and test the line after, that is a different story. But around here you have to show the gas company your permit and pressure test results before they will pressurize the lines.

[908/930]

When you pull a permit ( if you are allowed in CA) you should be able to ask the inspector a few questions, you need to do some homework so that you have a good idea of what you are getting into, out here most of the code books are available to read at libraries. Once approved insurance companies should have no problems with it. There is pipe sealant made for NG you will need to use that.

If you are going through a concrete wall at any point the steel pipe needs to be protected, up here it does anyways.

Depending on what pressure your gas service runs will change your pipe size, should say on the regulator. (Up here it is 2psi, and we do run copper tube.)

I'm not a gas fitter but was about to do my own a year ago, but didn't have the time.

[drkshdw]

I'm surprised you're allowed to do your own gas lines in California. Our codes here state they must be run by a licensed plumber, pressure tested by the plumber, then by the city, then by the gas company and then tested for leaks again by the city after gas is turned on. If one test down the line fails, you have to start all over from the beginning.

It's been such an issue that I am replacing gas appliances with electric. Too much of a hassle not to mention the $30/month fee just for the privilege of having gas service (before even being charged for the actual gas I use).

[red-beard]

I'm running into an issue with the local gas company in Montgomery County TX. I put in a 48 kW Generator in a different location and we ran the gas line about 5 feet from the generator fuel inlet to the pressure regulator on top of the concrete pad, then supported it.

The gas company person said we had to run it underground. Underground? The meter is 5 feet away from the generator. It makes sense to run it above ground, direct to the T at the meter. In this case, the pressure is 2PSI, and I have to put another regulator in place to the generator to drop it to 10" H2O.

This is "county" so no permits. It seems silly to trench 18" down around the generator pad and the over and up to the meter. And this whole thing is off-set from the house by maybe 50-60 feet.

Does this crazy?

[Brian 162]

I used to do gas piping. Black pipe was the norm. Do you mean you have to run 2 one inch gas lines to the appliances?
Couldn't you run a larger line to the appliances? Without knowing your gas code couldn't you size the pipe size to the btu input of both appliances?

[cabmandone]

Originally Posted by Tidybuoy

The A/C contractor told me that each device (Furnace & Tankless Water Heater) will need seperate dedicated 1" gas lines. He stated that you cannot run a single line and then T between the devices. He also stated that this actually makes it easier for them to pressure test the lines all the way from the meter to the units.

I'll make sure to add this to my long list of reasons I will never live in California. Totally pointless but a great way to increase cost and installation time.

You'll use black pipe. If you're going to have some cutting and threading to do, I'd rent handheld power threader and pipe vise, it'll save your arms some grief.

[billybek]

Copper can also be acceptable in some applications here.
Cannot remember the type but I think that in the states, it is not permissible. Could be the moisture content in the gas.
Black iron pipe is not rocket science to run. As mentioned above, it seems weird that you would need to run individual pipe to each appliance. A pipe large enough to carry the fuel required and accounting for pressure drop to where the appliances are located then branching off to each device is the norm here.

[David]

A quick search shows copper is allowed in Canada but it's special gas line and can only have flare fittings so not solder. I have replaced copper gas lines to water heaters that were completely clogged with black stuff.

[cabmandone]

For ease of installation, I'd check to see if the vinyl coated stainless steel flex tube is allowable with a manifold directly after the meter. I have been out of the business for a while but I think the only restriction is that you can't have a splice inside a wall around here.