What size propane line?

[fixerupper]

I'll be burying a propane line to a building Saturday and I'm a little inept at knowing what size to use. The heater will be no bigger than 150000 BTU. I'll probably end up with 100000. There will be about 250' of gas line between the tank and the heater. Is 1/2" ID about right? Or will 3/8 do the job? I'm burying copper and I was told schedule K is what I should use. Copper is $$$. Is there any other choice that's cheaper but still good? I want this up to snuff and I can pay the extra price for copper but a penny saved is a penny earned, so I've been told. Thanks.

I posted about this a few weeks ago, but I'm burying an air line too in a separate trench. I decided on 3/4" pex rated at 160 PSI@75 degrees for the airline. The airline will be galvanized after it's in the building. The pex will be inside 1 1/2" gray conduit in 10' lengths that I'm gluing together. The gray conduit looked like about the most economical at $3.62 per 10 foot length. The run is 140'. Looks like I'll have to gradually slope the conduit out of the trench on both ends but there's room do do it that way. Jim
 

[Ted in NE-OH]

I put in 1/2 in to my barn, only 50 ft from tank. Talk to your propane company they know the business. I got my pipe from my propane company and it had a yellow plastic coating on the outside.
 

[JDseller]

There is an aluminum and plastic combination line that the gas company uses around here. It is orange or yellow in outside color.
 

[upred]

Check with your supplier, but I think that with copper you need to use "forged fitting" they are heavier than the regular fittings. Why not just use one trench and then if you need to do any digging in that area you could locate both the air and propane. I would go larger on the gas line if there is any chance if Natural gas coming to you area (I just switched to natural and found that NG takes larger pipe than LP)
 

[Buster]

I put in 1/2 inch black pipe in when we built the house 15 yrs ago. Ran 1/2 inch under the house also, then ran the flex pipe up to the furnace and cook stove. I am in SW Missouri.
 

[fixerupper]

In a previous post someone mentioned a gas line couldn't be in the same trench with another line containing an oxygenizer (I think, correct me if I'm wrong). The other line is compressed air, sooooo! Using the same trench would only save me 50 feet of trenching and the trenching is being done real reasonable. (family member). Jim
 

[MarkB_MI]

Talk to your propane supplier. I haven't had propane for fifteen years, but as I recall we had two regulators, one on the tank and one at the house. Plastic line, about 3/8" ID, was buried between the tank and house, and iron pipe was used after the house regulator. I hope you're not planning to take the low pressure gas from inside your house and run it through a 1/2" line for 250 feet. Tell your propane company what you want to do and they should be able to set you up with a much cheaper solution than copper, and one that will work. They may even be able to run the line for you without trenching.

I do know that 1/2" pipe is going to be on the small side for a 150K Btu heater. 3/4 inch is typical for a furnace connection. This is for the final connection, after the second-stage regulator.

A 140' buried air line sounds like trouble to me. Unless you're going to bury it below the frost line, I'd drop that idea.
 

[Jake 2]

Have you considered a second propane tank at the new building? Would be more efficient and easier to keep track of your expenses.


Jake 2
 

[El Toro]

You should check with a plumber using Wardflex piping that's a flex stainless. They can determine the proper size. Only a plumber can buy it where I live. Hal

 

[fixerupper]

Thanks for the input. I have considered another tank and it might not be much more expensive than doing this. If I do go with another one I will have a total of three propane tanks cluttering up the farm. I'm just trying to keep things simple, both for looks and billing. Seems like my supplier has a fast turnover in drivers and we're constantly having a problem with a new driver billing the two tanks I do have wrong. The tank I plan to use serves the other shops too and when it's filled it goes on a separate bill from the house tank for tax purposes.



The underground run is somewhere around 150 feet. The rest is inside the building and unfortunately the heater is in the opposite corner from where the trench will meet the building. (40X48 building) I use 1/2" copper for other heaters, up to 150000 btu. and they don't seem to be starved, but this is a long run between tank and heater and I'm grasping for straws when it comes to sizing. I would like to have full tank pressure in the line with the regulator at the building but I'll check what's on the tank now. Last summer the gas supplier changed all of the regulators because the old ones were too old for insurance regs. I have a suspicion they might have put a regulator on the tank. I'll have to check that out.
I'll check it out with a gas supplier. The supplier I use now is a local farm co-op and as far as I know they only deliver. I don't think they do installations.Jim
 

[Mike M]

I had to go around 150' to my building. They make a plastic line just for propane.Mine is heavy yellow plastic. I think it is 1/2" ? not sure though. Check into it with a propane suplier it was not too bad $$ wise. special fittins for the ends and an armor covering for where it goes up though the ground to help protcet from mowers and weed eaters. Many won't sell it to you they want to do the whole job. I found one who would.
 

[fixerupper]

Thanks mike. Just talked to my son and he thinks he knows a guy who can get about anything, and he's family too. (Marilyn's from a BIG family) I told him about the yellow plastic so it's in his hands now. Jim
 

[showcrop]

About the gradual slope. You could consider using two 45s in order to have a gradual bend and have the pipe come up vertically.
 

[LJD]

I just installed a 300 foot propane line and got it inspected. 1/2" OD line good for 200,000 BTUs. You need a hi-low system. 10 PSI regulator at the tank and a 2 PSI regulator at the house or shop.

1/2" OD plastic-covered coppper made for direct burial propane at 250 feet is good for 222,000 BTUs.

Just pay attention to any copper you buy. Some is sold by the ID size and some by the OD size.
 

[El Toro]

They used 3/4 Wardflex on my Kohler generator. You need to check with a plumber that does this. Hal