liquid emerging from the coil 32 will flow through the supply pipe 53 through an open shutoff valve 54 through an appropriately positioned flow switching valve 55 and into the solar collector panel 52 through an inlet pipe 56 to divert the liquid flow into this path the outlet pipe 43 from the coil 32 is provided with a shutoff valve 57 downstream of the connection of the supply pipe 53 therewith after the diverted liquid has been circulated through the solar energy collector panel 52 it will emerge therefrom through an outlet pipe 58 through an appropriately positioned flow switching valve 59 through a shutoff valve 60 located in the return pipe 61 the return pipe 61 is connected to the outlet pipe 43 from the coil 32 downstream of the shutoff valve 57 the diverted liquid having thus been returned the outlet pipe 43 will be directed into the heat storage tank 12 through the return pipe 45 as hereinbefore described it will be noted that the addition of thermal energy to the heat storage tank 12 may be accomplished simultaneously with the heating cycle of the air handler device 30 and the circulation of liquid necessary to accomplish both of those functions is provided solely by the pump 34 to supply thermal.