Propane Distribution Plumbing

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Propane Distribution Plumbing

Postby dio449 » Fri Jul 06, 2018 7:01 am

I am planning to have a 40lb propane tank mounted on the tongue of my trailer and I would like to distribute the propane to a couple of points on the trailer at the rear. On one side I will have a fold down that will have a propane burner built in, and on the other side, I would like a connection point for a future hot water heater. I will be using black iron pipe to run propane from the front to the galley, at which point I will split the feed to the two locations.

So my question is if the two appliances have different pressure requirements I will need a dedicated pressure regulator at each appliance. Is it ok to run the distribution plumbing right off the tank with no regulator in between? Or should I put the regulators at a tank manifold and run separate lines from front to back for each appliance?

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Re: Propane Distribution Plumbing

Postby Ottsville » Fri Jul 06, 2018 9:15 am

I would avoid running a full pressure line to regulators at each device. Given some type of failure your whole tank will dump its contents at high pressure. I would consider looking for units that run on the same pressure. You may be able to run the lines with a regulator for the higher pressure device at the tank and the lower pressure device at the device.

Why use one 40lb tank? Two 20's, though a bit heavier, are easier to deal with and can be swapped out anywhere while travelling.
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Re: Propane Distribution Plumbing

Postby KTM_Guy » Fri Jul 06, 2018 8:25 pm

I have the same problem with needing two different pressure regulators, but I will have my tank mounted to the side at the back and use a wye fitting.

You could put and adjustable regulator at the tank and adjust it so you can run both on full. I think I would put a wye at the tank with your regulators and run two copper tubing runs to the back for the heater and burner.

I wouldn't put iron pipe in a trailer. The pipe is fine but the connector are cast iron and don't hold up well to vibrations and shock. and it's heavy.

Otts brings up a good point about the 20# tanks you can exchange almost anywhere and 24-7 at a lot of places.

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Re: Propane Distribution Plumbing

Postby Andrew Herrick » Wed Dec 19, 2018 11:34 am

Old thread, I know, but a little more information.

Per code (which I know isn't law for the homebuilder), the propane system pressure must be reduced to low-pressure (defined as maximum 14 inches water column, or about 0.5 psi) within five feet of the propane cylinder. You also can't run any high-pressure propane lines inside a camper. High-pressure would be defined as above 14 inches W.C., which might be 10 psi (first stage regulated) or up to 312 psi (maximum unregulated cylinder pressure). And you have to support and protect your piping (whether black iron or copper) properly.

There's a lot more rules, but that's somewhere to start. Whether you use a trunk-and-branch or home run system, the propane needs to be reduced to low pressure vapor before shuttling it to your appliances. Otherwise any leaks will pile up real fast! :frightened:

I vote for the double 20 tanks, too. You can use an automatic changeover regulator, which allows you to run your system off either tank while filling up the other one.
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