Ahem, help me with my gas issue…I’m in the process of rehabing an old home. All new gas lines (flex stainless steel) will be installed from the meter on…I’m trying to get an idea of main gas line size I’ll need coming off the meter for the following situation.
Current Appliances:
- H2O heater (40K BTU)—downstairs
- Heater (100K BTU)—crawl space
New Appliances Definately Being Added:
- Gas Fireplace (16.5K BTU) upstairs
- Heater (60K BTU) in the attic—Note: This is the unit that is (will be) furthest away from the meter (70 feet)
Possible Future Needs:
- Gas Dryer (22K BTU) (downstairs)
- Gas Range (120 BTU) (downstairs)
- Gas BBQ (57K BTU) (outside)
- Gas Fireplaces (two) (64K BTU total) (downstairs)
Total Possible BTUs = 479.5K
Thanks for the input !
Replies
Are you doing the work yourself?
I had the gas company recently repipe my house with flex stainless steel. The flex line delivers less BTU than black pipe (gas guy had charts showing BTU from certain pipe). My load is 650 kBTU, and I was upgraded to a 2lb system. They used all 3/4" flex line and black pipe nipples. Normal systems run 1/4 lb or about 7" water column (w.c.). Going to a 2lb system really helps keep the pipe size reasonable. At minimum the gas company will have to replace your meter and you will have to have regulators in strategic locations to step you down to 1/4 lb for the appliances. I happen to have 4 regulators and will need 6 total when I am all built out.
Also the meter has to be sized for the BTU load. I had actually been upgraded to a 2lb system about a year ago when I had my service relocated, but they had to swap out my meter for a bigger one when I added appliances recently.
MERC.
DJ and I--Thanks for the feedback
DJ--
I won’t be doing the work myself—I have a plumber friend who is helping me out (I’ll be doing a lot of the grunt work under his direction and buying the materials). I need to pull the permit/submit plans.…Everything has been approved by the Building Dept. (electrical, framing, plumbing, etc) except they want to know pipe size/total btus/ and length of runs.
When you upgraded to a 2 pound system, did the energy company upgrade the meter for free? I heard that PG&E will do this, but I haven’t checked yet.
Thanks for the info!
Yes, in NC, the gas company dealings are regulated up to your side of the meter. So when I had service moved, it was a well defined price. My monthly bill has some $10 charge (everybody's does) that is basically a physical plant fee - meaning their equipment on your site. So the meter all comes wrapped up in that. It was a good thing too because they had a bad meter, then a bad regulator, then some other problem. The guys were very good to me and slipped in some inside the house work under the "fooling with the meter problem" hours to make up for the nonsense involved with the meter (slowed the whole job down).
So at any rate, the 2lb system should be essentially free to you. My rate doesn't increase or anything, actually my therm rate goes down the more gas appliances I put in (mine went down 3% or so when they tallied my load - I went from 200k to 600k).
MERC.
natural I suspect....
make that less beans and you should do OK....
1-1/4" feed
1" trunk...
3/4" supply...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
You need to know the BTU content per cubic foot of the gas, and you need to know the distance in feet that each appliance is from the regulator. You could get your total 479 BTUH thru a 1" pipe, as long as the total run is a hair under 20 feet, but more than that you need to go 1-1/4". The 60K BTU heater will need 1/2" pipe capacity all it's own to get to your stated 70 feet.
You'll probably be running a fair amount of 1" with some 3/4" mixed in for short runs to single appliances.
The table I'm looking at is in CodeCheck, but I'm sure you can get it lots of places. They are quoting IRC T2412.3(1).
Also, I'm not a big fan of the stainless tubing. A guy I worked with shot a nail thru it once. Black pipe is much tougher.
"Also, I'm not a big fan of the stainless tubing. A guy I worked with shot a nail thru it once. Black pipe is much tougher"
Was it nail plated? The guys that did mine were very cautious about this. They nail plated everywhere and left if floppy in the walls. They also put the SS flex line inside a larger SS flex line inside the walls. I have spray foam insulation and it really locks it in place, so I hope my sider doesn't hit it (ceder shingles so lots of nails).
MERC.
I don't remember the exact circumstances. It was a kitchen with SS flex gas line run in a 2x4 interior wall to the oven. Bottom line, guys nailing on trim and siding can hit things in the walls, even if the plumbers and electricians are diligent about putting up plates. A gas leak inside a wall would be... unthinkable... and besides, most of the plumbers I know are happy to run black pipe. The flex is cheaper, easier, less safe... although perfectly safe in some applications where it has no chance of being damaged. I guess I don't use it because I don't have to.
From what I hear from local inspectors SS flex is preferred over black iron in some cases. Near the ocean or in some local conditions corrosion is an issue. Also, even though Florida doesn't get many, the flex has advantages in earthquake prone areas. Seems houses tend to dance and shimmy when the ground moves. Even those designed for earthquakes. This movement can rip apart and split the rigid connection in the black iron pipe. The flex sways with the house remaining unbroken.