The Rinnai 105002002 Water Heater PC Board is used to control and coordinate the electronic functions of the water heater for consistent operation. This printed circuit board processes signals from connected sensors and system components, managing functions such as ignition sequences, temperature regulation, and heating operations. It monitors operating conditions and sends commands t... https://www.hnkparts.com/rinnai-105002002-water-heater-pc-board-27113/4-105002002.html