Free hot showers for the past three weeks. The weather outside is cold enough to keep the wood cook stove fired up almost twenty-four seven to heat our home. With the wood cook stove heating the home, cooking much of our food, and heating our hot water, we have been able to wash dishes, do laundry, and take showers without using propane.
My favorite part of our off grid home is our wood cook stove during the winter. It is the heart of our home keeping us warm, supplying our cooked food, and heating our domestic hot water throughout the home. The wood cook stove does not have a reservoir instead it is plumbed into the domestic hot water supplied to each faucet in the house. When we turn on the hot water faucet at each sink or even the laundry machine, the hot water is derived from the wood cook stove.
Even though the wood cook stove’s setup is one of my most successful ventures on our off grid home, I cannot explain how much in trepidation I had when hooking it up. I was on a few websites that warned profusely that I was creating a potential bomb that could blow my family up. The scary thing was that if I did not hook the system up correctly, I could very well have endangered my family and our home. I kept researching and one person warned me that whatever I do, I must include a T & P valve (Temperature and Pressure Valve) correctly. I bought one that would open once the temperature of the water rose to 150 degrees Fahrenheit. Once it reaches that temperature, the valve opens and releases very hot water into a 5 gallon lidded bucket. I drilled a hole into the bucket’s lid to snugly fit a 1/2″ copper tubing, so the hot water would be safely contained. Currently, our T & P valve has only opened once without us even realizing it. When I was cleaning the stove, I discovered the bucket that contains the blow off had about a gallon of water in it. Some of this I already stated in a previous post “Domestic hot water from a wood cook stove, now that’s a hot idea,” but repetition on safety never hurt any one, frustrate them yes, but never hurt them.
Why is a T & P valve important? Well, without it, the pressure in the water tank or pipes will continue to build pressure from heated water and steam. If the hot water is not used on a regular basis the tank or pipes could explode under the force of the steam. Boom! The other reason is we decided to use PEX piping throughout our house. PEX does not seem to like temperatures above 175 degrees. The PEX pipe could be heated to a point that could cause it to fail, weaken, or even melt. I, therefore, put the T & P valve right before the water system converts to the home’s PEX plumbing line. The T & P valve keeps the system an open system, not a closed system. A closed system is very bad when heating water, very bad unless it’s Archimedes steam cannon.
Our hot water system has worked perfectly for the past three years. I remember testing the newly installed system on August 17, 2013. We are now successfully running 3 years on the system without a Boom!, but with an “ah” for hot water.