The Rheem-Ruud SP21236B Display Control Adapter Kit G4-5 is a replacement control accessory designed to connect the display interface with internal control components in compatible Rheem-Ruud G4 and G5 series HVAC/water-heating equipment. It works by enabling reliable communication between the user display and the system’s control circuitry, allowing settings, operating information, a... https://www.partshnc.com/rheem-ruud-sp21236b-display-control-adapter-kit-g4-5