Abstract: The three port two-way diverter valve includes a generally T-shaped valve body having one input and two output ports connecting to its hollow cylindrical interior. A cylindrical diverter valve member is rotatably disposed within the cylindrical interior of the valve body. The cylindrical valve member is closed at one end and open at the other with the open end disposed in fluid communication with the input port at the base leg of the T-shaped body. The diverter valve member includes a side port of generally semi-cylindrical shape such that when the side port of the valve member is rotated into alignment with one or the other of the two other output ports, the flow entering at the base leg input port is directed through the respective output port disposed in alignment with the side port in the cylindrical valve member. In this manner, the flow entering the base leg may be diverted to either of the output ports, as desired.