The PL6 is a 1/2" carbon steel continuous plumbing used for a continuous sampling of a boiler (see diagram) The lower orifice bleeds a small sample across the sensor. The upper orifice is used with the motorized ball valve and opens when the conductivity is above set point.
All you need is a controller, a sensor and a motorized ball valve, so you can complete an automatic surface blowdown system.
