Thread: Hot water system / heat exchanger shower

Originally Posted by DJL9999

126deg C from the main pipe , where there is a crap load of space, just before the big muffler box or cat whatever it is which it was 86deg. 74deg at the tip - after a quick 6min drive up the road and back. I think it will generate enough heat for a 38-40deg shower at a reasonable flow. I'd say I could get quite hot water from it slowing the flow rate down to wash hands etc.

After the rain dries up I'll get some copper pipe and give it a go.

Might be a few weeks on this one

Make sure you get the wind of the coil for the correct flow direction

Originally Posted by DJL9999

Might be a few weeks on this one

Ah, hot showers would be priceless for winter. Hope you can make this work so I can copy it!
Nearly every stop we've been to has had some sort of water available even if not drinkable so i was just going to bring along a spare empty 20l water container and fill up on site.

Even though its for a D1 im doing a setup on mates car using the item you pictured at start and i made a sill tank which will have water pump through the exchanger and has a thermostat so you can check temp. This means he can pre heat his water before pulling up and have 35liters of hot water

Ok. Admire the initiative being displayed and the Blue sky thinking.

So, How do I put this without coming across as sounding negative.

- The D3/4 exhaust runs so cool beyond the Cat you won't be able to generate sufficient heat via a coil in 1, 2, 3 passes to make it Tepid let alone warm.

- Clamping copper to the exhaust will accelerate corrosion and failure of the exhaust

- weight of pump, heavy copper tubing, hoses, fittings etc will easily outweigh the weight of a portable unit. And you'll be stuck with it there all the time.

- bugs love warmth - you'll need to flush those pipes dry or bacteria will thrive.

- idling to attempt to produce heat will do nothing positive for your engine, rather it will glaze bores and dilute oil.

Something like an Aquacube, at 6.35kg plus a small bottle of LPG will see hundreds of showers, can be removed when not in camping mode and will not hasten the demise of the Engine or Exhaust.

Warm water is dangerous when it comes to bacteria, think the real bad stuff! So a tank is also not the best idea for warmed, then cooled, then reheated etc water.. especially not if you're planning to wash (and potentially end up ingesting) with it.

Apologies.....

Here's a far more effective D3/4 option...

Source a Factory Webasto heater.....
Fit a pump...
Fit a switch...
Install fittings for suction and shower.

Originally Posted by Tombie

Ok. Admire the initiative being displayed and the Blue sky thinking.

So, How do I put this without coming across as sounding negative.

- The D3/4 exhaust runs so cool beyond the Cat you won't be able to generate sufficient heat via a coil in 1, 2, 3 passes to make it Tepid let alone warm.

- Clamping copper to the exhaust will accelerate corrosion and failure of the exhaust

- weight of pump, heavy copper tubing, hoses, fittings etc will easily outweigh the weight of a portable unit. And you'll be stuck with it there all the time.

- bugs love warmth - you'll need to flush those pipes dry or bacteria will thrive.

- idling to attempt to produce heat will do nothing positive for your engine, rather it will glaze bores and dilute oil.

Something like an Aquacube, at 6.35kg plus a small bottle of LPG will see hundreds of showers, can be removed when not in camping mode and will not hasten the demise of the Engine or Exhaust.

Warm water is dangerous when it comes to bacteria, think the real bad stuff! So a tank is also not the best idea for warmed, then cooled, then reheated etc water.. especially not if you're planning to wash (and potentially end up ingesting) with it.

Apologies.....

Some good points. The final one I do will be out of food grade stainless I think and a flange bolt in device ahead of the cat after testing etc with 10/12 copper wraps of 3/8 tube, but you've raised some interesting things to make sure I work around. The safety/heat pressure valve is the most important part I feel and I'm researching if it should be on the cold or hot side and where it vents to. Flushing out the system I do with the joolca and cube anyway now, as I'm all to away of 38-40deg bugs but generally speaking I'm hoping to pull 60deg+ and cool it with a mixer tap at the end like in the house etc. fair bit of work but time will tell .

I shall watch with interest