View Single Post
Old 09-21-09, 09:44 PM   #4
bennelson
Home-Wrecker
 
Join Date: Sep 2008
Location: SE Wisconsin
Posts: 546
Thanks: 3
Thanked 165 Times in 96 Posts
Default

I did some more work on the heat exchanger today.
(Yes, I am planning on insulating it...)

The next big challenge is to get it to connect to the electric water heater through the heater element ports. Those are straight threads with a gasket. Regular pipe threads will not seal properly into it.

At the hardware store, I was able to find a pvc conduit connection that had straight threads and a flat surface where an O-ring could be added. I got a pair of those, along with a chunk of 1" pvc pipe, and two pipe to 1" pipe thread connectors. With all that, I could make a plastic adapter that would go from the water heater to the heat exchanger.

However, I still had to solder on the dielectric unions. These allow me to transition from copper to steel pipe, without getting lots of corrosion at the point the two metals meet. A union is also a point where you can unscrew the unit. It would be very difficult to attach to the water tank otherwise!

Here is the union soldered in place. Note that it uses a gasket inside against the flat surface. That's similar to how the water heater elements connect to the tank.



Heres the adapter that I made to fit the heat exchanger to the tank.


A #34 O-Ring looked about right for it.


The O-ring slides right on and HOPEFULLY squishes in and seals to the tank.


You can see that the arm of the heat exchanger has gotten rather long. Oh well, easier to shorten than lengthen.


Not one but TWO sections of insulation are to go around the heat exchanger. I happened to have a piece to fit the 1" copper tube, and had another chunk that fit the first piece of insulation. I put the one part on, and then the second over the top of it.


When installed, the entire heat exchanger will be well insulated.

I still need to add some fittings to the end of the 1/2" (inside) pipe so that I can connect them to a pump and solar panel. I also need to attach a thermometer to the input of the heat exchanger and inside the hot water tank, so that I can see how much energy is coming from the solar panel, and how much of it actually gets into the tank.

So far, none of the parts have been overly expensive to hard to find, although some hardware stores have better selection than others. I stopped at a MegaStore today that carried 2" and 3" diameter copper fittings, but those get expensive real fast!

You will also notice that I am not taking photos in my driveway for once! Nope, I traveled over to a friend's farm where they are doing sort of an informal co-op on building wood gasifier technology. The guys there are supportive and have far more soldering experience than I.
I also managed to get a free 5 gallon bucket of apples and pears to run through my solar food dryer.
__________________

To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
bennelson is offline   Reply With Quote