Heat exchangers

[johndoe]

What is the difference between the heat exchanger in my water heater, and a heat exchanger used for blowing hot air (heat) into the cabin areas...?

My heat exchanger for the hot water heater is using engine water, (which is raw water) to heat water while running...
I want to add heat to cabin, (air) while running using the same concept, but the heatercraft and other manufacturers, don't reccomend raw water in these heat exchangers, expecially if running in salt... or brackish

Is it just a matter of flushing regularly, or is there a model that is less sucseptible to corrosion?

Perhaps a used water heater or exchanger modified to work with a 12volt fan and some tubing?

 

[DJ]

Re: Heat exchangers

Your water heater is probably stainless steel inside. It can handle raw water and salt.

Water to air heat ewxchangers are usually copper or aluminum. Raw water and salt will ruin them in a hurry.

They might last a while.

Why not run a seperate closed loop from your water heater? You'll need some type of a pump, but that should be easy.

 

[johndoe]

Re: Heat exchangers

thought about that option.... not sure what kind of pump to look at, but since we rarely use hot water on my boat, this is a viable option.... and could still provide heat when motor is not running...hmmmmmmmm..

why not a stainless exchanger built around a fan and enclosure wiht a multi speed motor..?
hmmmmm

cost is an issue... don't want to spend money on a red dot or heatercraft setup to have it corrode away in a year or two... but stainless heat exchanger is probably substantially higher in cost...

 

[cprimm111]

Re: Heat exchangers

Does the motor have a heat exchanger on it?
If so just plumb it to the "clean water" side with the coolant in it. That is might be how your water heater is done as well.

 

[Haut Medoc]

Re: Heat exchangers

This thread is a year old, I figger he has figgered it out by now.....​