Guys,

I'm looking at adding solar pre-heating to my water heating system. Here are the options I'm considering:

Store bought glycol based circulating/storage/heat exchanger.

Home made glycol based circulating/storage/heat exchanger.

Store bought batch heater.

Home made batch heater.

I'd like to hear advantages/disadvantages, ways to protect the batch system from freezing, reputable supliers of equipment or plans to build-it-myself.

Thanks!

Oh, I will add that I have a propane fired conventional water heater that lives in an insulated hut on the back side of the house.

__________________
-Evan


Benz Fleet:
1968 UNIMOG 404.114
1998 E300
2008 E63


Non-Benz Fleet:
1992 Aerostar
1993 MR2
2000 F250

I can tell you that you have them listed in order from most expensive to least expensive.

I am just in the middle of installing a thermomax system on my house. It is a glycol based vacuum tube system. The reasons I went that way is because I have an electric water heater. I have electric because I don't like the idea of a pilot light in my basement because of air quality issues. I installed the electric heater about 3 years ago. I would have preferred a nat gas direct vent tankless heater, but I couldn't find anyone to install one.

I will get several rebates for installing my system, so that was really what got me to do it. I will get maybe $2500 back on a $7000 system. So my plan for really cheap hot water goes like this. Thermomax system plus electric back-up heater. The electric heater is on a timer. My hydro utility will soon allow time-of-use billing. The electric heater will only turn on during the night when hydro will be dirt cheap at 2.7 cents a Kwh