Indirect Drain Back Solar Water Heater


	Drain Back Solar Water Heaters

Indirect Solar Water Heaters

Guardian DB (drain back)

The Guardian DB is an indirect drain back solar water heating system designed to accommodate climates where freezing weather occurs more frequently. The solar storage tank and the solar collector(s) do not differ from the Guardian direct solar system, the only difference lies in the way that the water is processed through the solar collector(s). Rather than circulating your potable water directly through the solar

collector(s) and back to the storage tank, your water is heated indirectly through a heat exchanger contained in the drain back tank. The Guardian DB utilizes two circulation pumps. One pump circulates water through the solar collector and back to the exchange/drain back tank. A second pump simultaneously circulates water from the solar storage tank into the exchange/drain back tank transferring the heat from the water that is being circulating through the solar collector(s) to your potable water. The system is freeze proof because all the water in the solar loop drains down into the small heat exchange/drain back tank when the solar circulation pump is turned off by the automatic controller. With no water remaining in the solar collector(s) or solar plumbing, no freezing of the system can occur. The indirect drain back solar system is the most efficient solar water heater design for climates that experience frequent freezing conditions.

Indirect Drain Back Solar Schematic:

Follow the blue arrows from the bottom of the solar storage tank as they rise up the cold water dip tube. This water circulates up through solar collector(s) and back down to the heat exchanger contained in the small drain back tank. As the water travels through the exchanger coils it transfers its heat to the surrounding water in the drain back tank. This water then continues down the hot water dip tube to the solar storage tank. Simultaneously the water within the solar loop is being circulated from the drain back tank up to the solar collector(s) and back again. The automatic controller powers the pumps to circulate the water continuously as long as sun is available to heat the water. The controller will turn off the solar system if no heat is available from the solar collector(s) or if the solar storage tank has reached its high limit shut off temperature.

The LeverEdge has been manufacturing Guardian Solar Water Heating kits for more than 25 years. Solar water heaters can involve quite a number of components if constructed in a thorough manner. The LeverEdge provides a simple solution to the complexity of these systems by packaging them in kits. The Guardian DB solar water heater is a complete kit that includes all of the components (large and small) necessary to complete the perfect solar water heating system. But that's not all! The Guardian solar water heating system also comes with many of the components already prefabricated which dramatically reduces the time necessary to install the system and virtually eliminates mistakes by the installing contractor.