Waukesha's thermostatic valves are piped to either "blend" or "divert" flow. A single valve may be piped either way, to achieve the desired effect. The technician assigned to start up a unit should verify proper port orientation. In the schematic shown above, the valve is a "diverting" valve. Flow through port B is always Bypass flow. Flow through port C is always going to or coming out of the Cooler. Port A is always the common port, All flow.