Outdoor Hot Shower

This is my entry for the #vanlife contest.

It will also give you an alternate use for your tire compressor.

I don't live in my van but I work from it every day, I regularly work on construction sites and quarries. It is nice to have access to warm running water to wash my hands and clean down my gear.

This device would also be really handy when staying in your van or camping.

WARNING: This instructable involves a heater, this unit has no thermostat so will not stop heating the water without intervention.

Also, the container is pressurized with no relief valve, failure to monitor the pressure in the container may result in rupture and possible injury.

Step 1: You Will Need

For this instructable you will need:

• 20L water butt
• Bicycle inner tube
• 12V immersion water heater
• Utility shower
• Epoxy resin
• High temperature sealer
• 12V power pack with an air compressor

Step 2: Prepare the Pressure Cap

As an alternative to a water pump, I opted to use my tire compressor to pressurize the vessel.

Starting with the inner tube, cut out a section around the valve.

Trim down the surrounding rubber until the valve fits inside the lid of the water butt.

Drill a 9mm hole in the center of the lid and insert the valve.

Using epoxy, bond the valve into the lid.

Use a spacer and a clamp to apply pressure, allow the epoxy to cure before applying any pressure.

Step 3: Install Water Heater

Remove the installed tap by unscrewing it.

There is a backing plate in the hole which has to be cut out.

The water heater is too large to fit through the hole from the outside so it needs to be fished through the neck of the container using a heavy electrical wire.

The heater is pulled backward through the hole and fixed in place with some high-temperature silicone. Again this should be left to fully cure before pressurizing the container.

Note: the sealer used here is not food grade so the water from this unit is not suitable to drink, there are sealers that are food safe if you want to be able to drink the water.

Step 4: Install the Tap

Drill a 10mm hole in the side of the container, I placed this at about the 5l mark on the container. This allows the heater to remain submerged as to expose the element could result in burning it out.

The tap can be turned off to allow you to remove the hose during transport and filling, making it a little easier to handle.

Step 5: Test

I filled the tank to about 10l for the test.

I hooked the heater to the 12V outlet on the power pack and allowed to heat. It took about 30mins for the water to become noticeably warm.

I then connected on the air line and pressurized the container. I worked in steps stopping to test pressure at 10, 15, 20, 25 ad 30psi. The container swelled significantly after 25psi. At around 20 the pressure from the outlet was pretty good.

Please note you should heat the water prior to pressurization as hot water will further expand and may push the pressure to the point of rupturing the container.

Step 6: Problems, Thoughts and Future Ideas

In the early stages of testing, I over pressurized the container and sprung a few leaks. Releasing the pressure and emptying the tank, repairs were easy and I got to know the limits of my tank.

The tank needs a temperature gauge, I was thinking something along the lines of the stick on thermometers for aquariums but most stop at 40 deg C, if they go beyond this they just show black. I note this as during one of the tests I forgot that I had left the heater on and there was only about 6l of water in the tank when I released the water it was very hot and not at all nice to have pour on my hand!

As the pressure in the tank drops so does the outlet pressure. To counter this I ran the compressor constantly but if you are not siphoning off the water pressure you need to stop the compressor to stop the tank bursting. If there was a pressure release valve this would take care of itself.

Comments

[AbieJMartin]

Great idea. I am about to come up with a solution myself. I will use a pressure cooker, fit a valve to compress, use propane to heat and a hand pump or compressor to compress. For temperature it should be possible to fit a thermometer or do the hand test. It is also possible to fit an existing thermometer from a pot (eg. AMC Classic ones are very good)

[mdavenport1]

great use of the compressor and the bike tube. Good build.

[Left-field Designs]

thanks I'm glad you like it

[GergelyD]

Epoxy does not bond to thermoplastics permanently.

[Left-field Designs]

I wasn't aware of that. For now it seems to be holding fairly well, it's been in daily use for about 2 and a half months now but I will keep a close inspection, the last thing I want is a rupture.

[bbqandbeer]

this is too dangerous on many levels. much safer to use a prpane water heater and pump system.

[Left-field Designs]

Agreed, it has its dangers, hence the numerous warnings and suggestions for alterations incorporating safety features.

My aim here was to make something that did not require additional equipment in my van such as a pump or propane heater. The 12V heating element was small, cheap (E5) and easy to build in. I carry the power pack with the compressor all the time.

Compressed air is a common way to pressurize water:

https://www.amazon.co.uk/Hozelock-Ltd-4140A0000-Po...

for example, albeit that these are specially designed containers. I most likely should build a V2 with a specific pressure vessel but for now, this is good enough for me.

If anyone has any safety concerns that they don't feel are acceptable, then please don't build an exact replica of what is here. If there are suggestions for improvements, I would love to hear/see them.

[mosix]

I would not trust much to mount a tap on the wall of a bin of that kind.

[Left-field Designs]

I can't say it's been an issue, I put a large washer on the inside, behind the retaining nut and it seems to be fine. It was actually the only place that didn't leak when the pressure went too high. I take your point though, the walls are quite this.

[Swansong]

That would be neat to take camping :)

[Left-field Designs]

What's handy is that you can heat and pressurize it then disconnect from the power pack. I reckon the roof of a car or 4x4 would be perfect to get the required height to shower under, its only a little over 20kg when full so its easy to move.