View Full Version : Converting my Stove into a Water-Heater

8th January 2008, 12:21 PM
I live in upstate New York. Not everyone is lucky enough to live in rural America. I found a big energy-saver for those who do.

I have an electric water-heater, the 50 gallon size. Also I have two stoves I use with varying regularity for heat. In the basement is my wood stove. My rice-coal stove is in the living room.

Until last year, the only purpose for these stoves was to heat the house. Then, at www.hilkoil.com (http://www.hilkoil.com) I found a website offering a new kind of water-heater, called the "Thermo-Bilt Coil". Instead of using electricity, it uses the heat from a stove. Any kind of stove. I decided to install a water-heater in my woodstove.

The coil is a loop of stainless steel that mounts inside the stove. I cut two holes in the side, near the stovetop, with the holesaw bit included in the kit. I think the whole kit cost me less than $150. Thermo-Bilt provides a good set of instructions (which are written in the U.S.A.)!

Because my old water-heater tank is on the first floor, and the woodstove is in the basement, my revised plumbing takes advantage of passive water circulation, requiring no electricity, no pump, and no controls. The cold water flows downhill from the tank, then rises as the water is heated in my stove, and this happens again and again until the water in the tank is brought to the same hot temp as if it were being electrically-heated.

Now I get "free" hot water for the whole winter. When spring arrives I flip on a circuit breaker, and my electric water-heater takes over. It easily paid for itself the first winter, and for six months every year, it lets me stop paying the electric company for all of my hot water.


Tony From West Oz
12th January 2008, 10:51 PM
Congratulations on your successful "wet back" installation. These have been in use fro many years and do rewuire more fuel to heat the water and the house, but it is usually far cheaper than heating the water separately, by gas or electricity.


30th January 2008, 12:57 PM
I did a similar thing - purchased a piece of 3mm brass sheet. Silver soldered 25mm copper pipe onto it in a c format and installed it at the back of the fire box. Connected it to the hot water heater via 25mm pipe. Works well however as it get just enough heat to heat the water without ever boiling it.

The main danger is it is heating water under pressure and requires an adequate relief valve and steam ticket to operate otherwise it is very dangerous.

30th January 2008, 05:57 PM
an extention to the hot water heater idea.

Is to run piping thru the house and have them connected to water radiators so heat the whole house.