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cosmic63
Oct 21, 2009, 05:57 AM
How do I determine the size of black natural gas pipe I need in a rehabilitated house. Total length of run is 60'(stove). Teeing off at 40' for hot water heater and clothes dryer.
What size to start with, when to reduce pipe?
Thank you for your help.

KISS
Oct 21, 2009, 08:17 AM
Here you go:

Gas Piping Sizing Worksheet (http://www.naffainc.com/x/CB2/Mech/gaspipingworksheet.htm#GasPipeSizingTable)

The calculator is unclear whether it takes into account of fittings. From this website fitting loss is usually considered to be 1.5 * the equlivelent length of pipe.

Ref: http://www.engineeringtoolbox.com/natural-gas-pipe-sizing-d_826.html

speedball1
Oct 22, 2009, 06:17 AM
We don't use much gas in my area but back up North we brought our gas into the house with 3/4" black iron pipe. Regards, Tom

KISS
Oct 22, 2009, 07:20 AM
Yep, usually comes in at 3/4 to 1" and you might have some 1/2 inch branches somewhere. The heater is like 80' away. Dryer about 70'. Water heater about 75'

Then a oven/stove is about 60'
And another wall oven and stove at about 50' on same branch.



Don't forget the dirt legs on any appliances below the gas pipe entrace to the house.

So lets say it comes in 2' off the cellar floor. Te water heater and heater need it. The dryer gas entrance is too close to the floor to get one.

speedball1
Oct 22, 2009, 04:27 PM
KISS,
By "dirt legs" do you mean a "drip loop"? A 6" capped nipple that looks down from a tee and is there to collect moisture in the service line before it gets to the pilot lite?
We all have our "special names" for things inn our area. That was addressed a few posts ago with Milos "dirt arm", my "lateral" and Marks "Dandy Clean Out.
Cheers, Tom

KISS
Oct 22, 2009, 05:26 PM
Yep. Those things. I reserve drip loops for things electrical. You cable TV, thermostat wire, service entrance, telephone. Because those do loop.

Now if you called it a "drip leg", I'm OK with that because I don't see a loop.

And it's a place to attach a pressure gauge too.

Milo Dolezal
Oct 22, 2009, 10:11 PM
We use Gas load tables to figure out Total BTU load for your house. There are several variables that will tell you what size of pipe to use.

But based on 60' of developed length, I agree with advice of other Experts: 1" from the gas meter, tee off with 3/4" to stove and 3/4" to WH. Somewhere along the run, Tee off with 1/2" line for gas dryer.

And how do you heat your house ? No furnace ? No BBQ ?