Gas Line Sizing Help

[Milzo]

I am working on installing a gas line from my house to my barn/garage. A friend who is a full time plumber is doing the gas line install on the side. He is young and doesn't know how to figure the size of line I need. I've reached out to the gas company and Reznor and neither have offered much help. Wondering if anyone here knows how to do this.

I've already purchased 100' of underground poly 1" yellow gas line and 2 risers. Now I need to figure out what size black pipe needs run inside the house and inside the barn. The Reznor will be a 60,000 btu unit. The charts I've found lead me to believe 3/4" for the black pipe will work but I am not sure if going from 3/4' inside the house to 1" outside and back to 3/4" inside the barn works.

Any help would be much appreciated.

 

[59 wagon man]

you need to know the operating pressure of the system plus the amount of fittings to properly size the pipe

 

[Milzo]

you need to know the operating pressure of the system plus the amount of fittings to properly size the pipe

Can i get the operating pressure by looking at the manifold? I will draw a schematic with fittings over the weekend to get it more accurate.

 

[Milzo]

Did a quick ISO drawing that should be real close to accurate. Red lines are the new gas line to barn. Yellow is underground poly pipe. Does this help?

 

[Jackfre]

Distance of each leg, pipe size of each leg, input of each appliance connected and size of meter. Get a manometer and check the operating system pressure of the house as it stands now. See how it sits with one appliance operating and then fire each load, Is the system as installed maintaining pressure with all loads operating at the same time? Before deciding to add more you should make sure that what is there is ok for the existing building.

 

[polexican23]

i would pull straight from the meter and run a 1" line.

 

[b-boy]

My house was done this way. The plumber ran 1" off of a wye at the meter to the barn.
There is an exterior shutoff at the barn.

Inside the barn it's been downsized to 3/4" or 1/2" depending on the requirement of the appliance. I ran 1" as far as I could. My on-demand heater required 3/4". Everything else was 1/2".

 

[PCustoms]

If he doesn't know how to read the charts or runt he calcs himself, is he really qualified to hook this up?

 

[Milzo]

Will see if we can run another 1" line off the meter. Would still have to go through the house basement to get to the barn since we just had concrete drive poured.

PC - Yes he is qualified to install gas. He does black pipe, csst and poly daily for last 7 years. He typically works of a schematic provided by his office, this is a side job not going through his office.

 

[HoosierBuddy]

OK...the 1" PE is fine...in fact it's a bit overkill but it will work great.

The issue, as others suggest, is your current 3/4" line is pretty near maxed out if you have all of your existing gas appliances running and you "MIGHT" run into pressure issues on your heater IF or WHEN your other appliances run.

If your buddy has a manometer have him check your inlet pressure from the gas company. If it's 9-inches or more...I'd hook into the 3/4" and it will probably never cause you an issue. If it's 7"...I wouldn't chance it.

Also...while you're at it...look at your gas meter. Chances are it's a 250 meter...which will be rated at 250,000 BTU's per hour. Add up all of your other appliances...or at least as many of them as you think would ever be running at one time and compare. You may need a bigger gas meter.

Phil

 

[Milzo]

Thanks for everyone's comments. This morning I measured every gas run and updated the Isometric. I think the 250,000 CFH gas meter is going to be ok since I am at 254,000 if every appliance were running full blast. I will get a measurement on the gas pressure soon.

 

[D45]

I am way over BTUs also on my 250 CFH meter

Never had an issue either

 

[HoosierBuddy]

I am way over BTUs also on my 250 CFH meter

Never had an issue either

As I've mentioned before, I am as well and I literally walk past the people I could ask to upgrade mine every morning on my way to my desk.

A 250 will pass a lot more gas than it's rated for. What it won't do is accurately measure a lot more gas than it's rated for. My thinking is once your flow exceeds the meter capacity, you may pull down the pressure in the meter, causing it to speed up....meaning you would be slightly overbilled. I have never done any real testing to verify that though. It's just a hunch.

Phil