SKU: 10.7

10 year manufactures warrenty. A Thermosiphon unit is a completely passive design that relies on buoyancy effects to circulate fluid through the collectors as opposed to the pumps and controllers found in active systems. When sunlight strikes the collectors in the SunSiphon system it heats the food-grade antifreeze within them, which then rises due to buoyancy into the jacket-style heat exchanger on the bottom of the storage tank. Here the antifreeze transfers heat into the tank, becomes cooler, and sinks to the bottom of the collectors to repeat the process. During periods of no sun, the cool fluid in the base of the collectors is not heated, does not rise, and thereby stops circulation of the antifreeze. In this manner, thermosiphon units achieve the operational characteristics of active systems but without the pumps and controls. See www.sunearthinc.com for more spec. info