Home made heat exchange units

Johny,

This is sort of project I'd try, if I had the time. Just checked "home made heat exchangers" on Google, and there's about a gazillion photos of h/e's, though nothing automotive related.

You would need silver soldering equipment, and a former to make the heating coil(pipe would do). Would use 3/8" pipe for heating coil, rather than 1/2". Size and weight might be the killer for a home made unit, and by time you make one, it'll be as expensive as a bought one.

Good luck, put up some photos if you make one. Could always make one to work in a boiler, on the fire, and using your pump set-up.

Bob.

What's wrong with these?

http://www.glind.com.au/store/heat-exchangers/automotive-heat-exchanger

Automotive Heat Exchangers

Hi John,

If I was a plumber I may consider making my own heat exchanger but otherwise it could be tricky to source the necessary parts at the right price.
Heat exchanger construction articles are uncommon but here is one that you may find helpful.

Commercial exchangers are available without all the bits & pieces that you may already have in the junk box.

I wouldn't trust myself to make one - they have to withstand the 13 psi pressure of your cooling system and any sort of a leak might mean a cooked motor.

I have made them by making a copper pipe coil to whatever diameter and length you want and then fitting it inside a length copper pipe large enough in diameter to house the coil. the ends of the coil protrude out the ends of the tube, the end discs with an inlet pipe silver soldered in one and an outlet pipe soldered in the other, a hole the size of the coil pipe is also needed in the end discs, the discs are silver soldered to the end of the tube with the coil ends through the holes then they are also soldered.

I have often thought of using a heater core (radiator) from a car heater fitted inside a metal "box"not much larger than the core. Mount the core vertically inside the box with a partition attached to both the core and the inside of the box, the partition is to stop water from flowing around the outside of the core and thus forcing it through the core.
An inlet in one side and outlet in the other of the box and the inlet and outlet of the core protrude through the box (and soldered) for the fitting of hoses.

Geeeez it`s hard to explain things in writing. LOL.

One way of bending a coil so that it does not flatten is to anneal the length of copper pipe you are going to use,after it has cooled, block one end by folding it over, fill the pipe with water and starting at the sealed end freeze the water in the pipe in a deep freeze. It may not all fit in the freezer so do a bit at a time. Using a bit of scrap pvc or ?? with a diameter to suit the inside size of the coil, hold the PVC in a vice and wrap the frozen pipe (or section thereof) around the PVC until you have a coil. you may not get it all in one go so fill it with water again and with the first bit of the coil in the freezer first, freeze some more. There is no hurry to bend the coil after freezing the pipe because the ice inside has to be able to break and move along while you are bending the pipe. Even wiping a rag whetted with warm water along the pipe a little bit might help.
There is a fair bit of try it and see involved.

Good luck ,

Scrubby.

These are the best

Helton

Sorry but I can't see the point of going to the trouble when a shower pump in a bucket is so cheap, simple to use, takes up less space and weight and less time to set up.
On our trip to Cape York one of our group had a heat exchanger and we used it ounce the rest of the time we used a bucket with a shower pump.
The KISS principle is the best way to go, every time I stray from it I f-*-k up.

Have Fun

Hi Malcom,
I've had two of those $25 BCF or camp shop showers and yes I agree they are great "when they work" but I found the cheap pumps to be there let down so I installed a sureflow that had a great workout whilst we traveled all year in 2010,I basically did the same thing and boiled the billy over the camp fire but at one stage there was a total fire ban and had to use gas and I thought gee if it was ready to go all plumbed up that would be great hence the reason I'm looking at this option, besides my pump has so much more pressure and yes it uses more water but that's not a worry if a creek is right next to us,each to there own I suppose.
Cheers John.

I made up a flat stainless tube coil and mounted it in a steel box frame with some perforated sheet on top, off that I have a couple of hoses with large bore stainless and brass air line couplers. I also have a submersible pump with these same couplers inline about a third of the way to the shower head.

I use a large tub of water and recirc the flow through the heater until desired temp, I then disconnect and run the tub through to the shower head. I use the heater over coals, or mainly over my gas ring cooker where I can still heat a saucepan of water or similar while I heat my shower water.