Rinnai N Series PCB - (PN-700) The PCB on a Rinnai N Series water heater is the electronic control unit running every core function of the appliance — ignition, temperature regulation, fan operation, and safety monitoring. It's constantly communicating with the thermistors, ignition system, and gas valve to keep the appliance operating correctly and safely. When the control board fails or is damaged, the results are usually immediate and unmistakable: fault codes on the display, or the appliance stopping entirely. In many cases, replacing the control board is the only fix, since it sits at the centre of every other system it manages. This genuine Rinnai PN-700, built to the original specification, restores full control functionality and safe operation. ⚠ Important: This is a safety-critical electrical component and must o