Controlling Reheat Temperatures in Texas

Temperature control is a big deal in Pittsburg, Texas, where summer afternoons average in the mid-90s and frequently top 100. At AEP/ SWEPCO’s J. Robert Welsh Power Plant, however, the problem didn’t lie in the outside temperature, but in controlling the reheat temperature. The pneumatic actuators on the attemperator valves couldn’t smoothly control the valves at low levels, slamming back and forth between 10 percent open and fully closed.