Geothermal heatpump & re-circulation pump.

I'm installing a geothermal heat pump with a "hot water assist" (desuperheater). Which preheats the water in the water heater when the heat pump is running. Since my farthest bath is about 75 feet from the water heater I was planning on installing a re-circulation pump with a 3/4" dedicated return line. Since both the heat pump and re-circulation pump utilize the water heaters bottom drain valve to "re-supply" the water heater, can't I just T the the 1/2" heat pump line to the 3/4" re-circulation pump line? Do I need some check valves somewhere?