while designing solar hot water, total system flow rate as mentioned in help is the flow rate for the collector side. so how is the tank side flow rate taken care of? and also the pump is mentioned generally. the pump refers to the collector side or tank side? Also, in cases where load exchanges heat through exchanger and actually the tank side water is not used up ie only the energy is used up. so how then is tank temperature calculation affected? thanks in advance.
Please see the description of the solar water heating model in SAM's help system (click "Solar Water Heating" in the table of contents). It includes a diagram showing the location of the heat exchanger and pumps, and where in the system the flow rates are calculated.