Hello and welcome, if you are interested in a solar H2O system there are a few things you should know...Your proposed site should be clear of shading between 9am and 3pm or your solar array production may suffer. (See Site Assessment tab) Depending on your site, solar collectors can be on the ground or a roof mount system which is the most common system due to the added expense of having underground insulated plumbing and line losses.
Drain-back system, is a favored type of system due to longevity, efficiency and limited maintenance associated with them . This system will sense when the collectors are warmer than the water in the domestic hot water heater or storage tank and activate the collector pump to move the coolant (30% glycol antifreeze mix) up to the collectors where the coolant is heated by the sun then brought back to a heat exchanger. There is another circulation pump on the potable side that runs when the heat exchanger is hot enough to add heat to the domestic water. There are tricks to the proper operation of this type of system that must be followed, for example, the plumbing must slope to assure proper drainage otherwise a freeze condition may result.Pressurized closed loop with glycol antifreeze. This system remains flooded with a high concentration of glycol to prevent the system from freezing during cold months of operation. There is a loss of efficiency due to the higher glycol concentration and the fluid must be checked over the years for Ph changes and to assure that the minimum freeze temperature is adequate This system is not a good choice for areas that may have frequent power outages w/o power backup because the glycol will break down under high temperatures during stagnation. One advantage is that there is no need to slope the plumbing because this system does not drain and another is that a smaller circulation pump can be used.