This is a good one I have seen my uncle use something similar a this cabin in northern Wisconsin. Indirectly heat the water so there is no danger of over heating. My uncles method was to put a small 20 gallon electric water heater up near the ceiling but it is only used as a storage device. He then has a single loop of copper tube running down from the drain of the heater and into a T put in near the pressure relief valve. No pump, only convection currents. His coil goes All the way to the floor, up the back, then is suspended about an inch over the top of the burner. As long as there are no dips to form a heat trap the water will rise up into the heater as it is warmed. As the delta T nears equal the convection slows down and eventually the water stops circulating because heat is lost into the air around the coil just as fast as it is absorbed. Takes a little adjustment to get right but easy to do.
|