natural gas line chart Q..

[Spyider]

looking to do a natural gas PE hose install this summer. i got about 125' total, i don't know exactly what heater ill be using yet.. so i'm going to try and get 80,000 BTU available, just in case i find a good deal.
So my Q is..
i found one chart that said
3/4" hose = 95,000..
1" hose = 179,000..
then i found another that said
3/4" hose = 60,000..
1" hose = 117,000..

so what the hell... if 3/4" is going to be good ide rather use that its about half the overall price..

 

[Jarnipman]

I just ran a new gas line to my shop from the meter at my house - I had it inspected as well, and know at least what they want in my state of MN. There a lot of people that run copper underground and less PE here. In other states you would be keel hauled for using copper. Two big questions, length of pipe and gas pressure supplied by your gas company - if you have >2 PSI you can do a lot with it. My house is run of 3/8 ID for > 100,000 BTU and my shop 100,000 BTU runs of 1/2 pipe going about 100 feet or so. If you are running 7" w.c. gas pressure, you need a much bigger pipe and it costs more. Let us know your gas pressure, maybe it says it on your meter or you can call the utility company and the distance and I am sure there are are more than a few gas fitters here. The gas chart I use is free and accurate - google Minnesota building code, second link down and you can get to our mechanical code for free online - it's universal for the tables, but they are all in there for various situations. Hopefully, WI has their mechanical code online for free as well.

 

[classic boost]

don't forget that 90deg bends effectively add length to your calculations. that 125' can turn into 175' quickly. i would certainly err to the side of caution on this.

 

[tomroblee]

The btu capacity of gas pipe depends on a number of factors including the length of the pipe, the (inside) diameter of the pipe, the incoming pressure of the gas, the amount of pressure drop in the pipe run, the btu content of the gas, the temperature of the gas, the specific gravity of the gas, etc.

If you looked at two different charts and saw different answers, it is likely that the charts were based on different assumptions.

One likely possibility is that PE gas pipe is made in both IPS (iron pipe size) and CTS (copper tubing size). The actual inside diameter of IPS is larger than CTS for any given nominal size, so the IPS will have a much higher capacity. Examples are shown in a manufacturer's website:

http://www.slpipe.com/assets/PE-Yellow Gas.pdf

You don't say whether this is going to be a separate gas service or whether you are wanting to tap into the gas service to your existing house. If it is the latter, it is possible that your house is already using the most of the available gas. If this is the case, you won't get the results that you want even if buy bury a 6" line to your shop.

 

[2000xpsd]

Charts might of had different inlet pressures. If your coming off after the reg it's probably 8"wc. Check out gastite's chart, it's pretty good
https://www.gastite.com/downloads/pdfs/peinstallationguide_1.pdf

 

[CNGsaves]

Do NOT do anything smaller than 1" for sure. I'd go with 1 1/4" as the pipe is cheap and not much difference in price of the risers/shutoffs.

+1 that critical factor is your Inlet Pressure as normal residential NG pressure is 7 to 10 inches water column or around 1/2 psi. That's not much pressure so you want a BIG pipe out the 125 ft to shop.

Be sure to put in tracer wire so you can locate the buried yellow plastic PE pipe later.

 

[Spyider]

to answer some of the Q, i was looking at ips. right now i got about 1psi coming into the home. i didn't plan to add a second meter as i dont want to pay every month for it even when not being used. the ONLY appliance in my home using gas right now it the furnace..
i was hoping to tap directly into the meter... have it done whatever. yes ill have tracer wire in with it. its only 50feet from home to garage.. so yes that 125ft was with added bends and whatnot that will come with it. to be super safe ide say 150.. max!

 

[tomroblee]

I'm a retired gas utility auditor (bean counter) in Indianapolis, IN. I'm not familiar with the gas utility in your area, or with its standards.

In my area the smallest residential service and meter is good for 250,000+ btu per hour at normal pressure. If your furnace is 170,000 btu or less you shouldn't have a problem even if your pressures is much less than 1#.

In our area 1# pressure is rare as hen's teeth. The standard delivery pressure that I'm familiar with ranges from about 6" water column to 10" water column (about 1/5 to 1/3 psi). Most appliances regulate the pressure down even further. About the only reason that gas would be supplied at 1# pressure or higher is when the customer has CSST (corrugated stainless steel tubing) for interior gas piping. The CSST is smaller diameter than typical black pipe, so a higher pressure is required to provide adequate supply.

Quite often a local gas utility will have several employees who do small jobs on the side at quite favorable prices

 

[2000xpsd]

You might want to have a 425 meter put on...if it already isn't, I doubt it is tho. Should be free to do so. 1" line will be ok
I ran off the meter 260' of 1.25". Before the meter the psi is very high but the reg is set @8"wc. At my heater in the garage I have 7.5"wc. I've ran the heater full throttle for testing at 130,000btu without a drop in pressure

 

[Spyider]

well here is the exact meter i have on my home. http://www.imacsystems.com/ac250.htm .. other than that it looks like i got 1" black pipe coming into the home. it might be easier to just tap into that and bring it to where i want to exit the home and go from their. it would knock my trench down to about 70ft total then.. + whatever it would be on ithor end inside..
looks like i need to find someone that works for the gas company that wants to do some side work.. haha