The HTP 7700P-3100 Control Board PH76 is a replacement electronic control board designed for compatible HTP heating equipment. It processes signals from thermostats, sensors, and other system components to coordinate key functions such as ignition, heating cycles, and safety controls. This control board is used in compatible HTP boilers and water heating systems. It helps maintain acc... https://www.partshnc.com/htp-7700p-3100-control-board-ph76