DIY water system / shower build for expo trailer


I am looking at buying a small 5ft expedition trailer for extra storage for the family etc. I would like to add an electrical setup in the tongue box and a water tank and how shower setup. I have seen some units mounted to exterior in a pelican box......

can anyone post a link to a full build so that I can get my head around it. Thx


Active member
No build here, but the concept is fairly simple, the packaging a little more complicated.
A propane heater, camplux, Zodi or some other will heat whatever you pump through it at a rate that makes a passible shower.
A battery powered 12v pump like a Flomaster or Shurflow can do that from whatever water source you use, a jerry can, a built in tank or a solar hot water collector on your roof. These pumps pressurize the hoses behind a valve and will turn on again whenever that valve is open and pump until the valve is closed and pressure restored or the tank is empty.

Some systems, like the camplux, are on-demand, heating whenever the shower head is flowing. Others, like the Zodi, need the pump to stay on whenever the heater is on, so it is helpful to be able to put the shower nozzle back into the water supply or redirect it there while you soap down and save yourself some water.
Most showers should be kept as short/minimal as possible if you carry your own water. If you camp by lakes or streams, a long hose (to keep your source clean and soap-free) attached to the pump would let you shower until you run out of propane. You may have to fill the hose to "prime" it before the pump works, so a cap for one end would help as you connect it up.
Decide what parts you want to use and then find a box to fit it all in. Braided hoses like you find under your sink are readily available in all sorts of sizes and fittings, and are durable enough to use on the road. For the cost of a large Pelican box you can probably buy everything you need for your shower, so the importance of the portability of the system will depend on what you want to spend. Bolting everything to or in the trailer with a longer hose for the shower head may be all you need if the family you are storing is ok showering so near camp...


Long time off-grid vanlife adventurist
@llamalander provided a great write-up on how a propane fired on-demand hot water set-up works.

It is exactly what I have on my trailer, though attached, not portable. The armored black box at right rear inside of my trailer in the image below is an on-demand propane-fired water heater. It draws cold water from a 22 gal tank underneath the trailer via a 12v pump and sends heated water to two quick-connect locations; one under a rear corner for a faucet/sink, and another under a front corner to which I can attach a shower hose.

I extended my shower hose with an extra length so I have sixteen feet. That way I can run it into a privacy enclosure, or use it to wash gear more easily, etc.

Most small on-demand water heaters like this are electronic-ignition powered by a couple D cell batteries, so you won't need to worry about figuring how to wire it from a 12v power center.

I love mine. It has proven to be simple, easy to maintain, and problem free in the couple years I've used it, and I use it a lot. When I know it's going to get below freezing, I drain the system and draw RV anti-freeze through the lines and heater. At least once a year, I run a bleach solution through everything, including the water tank, heater, plumbing lines, and any containers and hoses I use for filling or around camp. See insta post below with the details on that.

I haven't felt the need for it to be portable or in a Pelican box. If I ever get rid of the trailer, or start using my van only for trips and not base camping with the trailer as much, I'll set up the same thing in the van, mounted on the inside of the back door or in a vented bumper box.



Let me know if there are any other questions I can try to answer.

Good luck, hope it works out well for you.

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Just to add one thought to the above post.

And a disclaimer. I own a Zodi, and love the way it works, sort of. The newer designs I like better...

The Zodi, while it works well, does NOT instantly heat up your water to showerable temps.

The way to use a Zodi is to turn the pump on, light the unit, adjust your flame, and then allow the water from the showerhead to recirculate into the source container until you reach the temp you want, turn the flame down to keep it from cooling off, and take your shower.

Most of the portable propane water heaters work kind of like this. I've never tried full flame though, it MAY get it hot instantly, I am not comfortable doing that though...

THe other issue with the Zodi is it is designed to stand on top of a 1lb propane bottle, OR be hung like a lantern... Wall mounting doesn't work safely with them...