Staff Answer
Sep 25, 2026 - 07:47 AM
Good troubleshooting so far. A tripped thermal relay means the boiler overheated, which is the reason for the 6-flash code. That usually points to a failing cooling unit, not two bad boards. See our 6 flashes / fire hazard article.
For a basic check of the board with a meter: confirm 12V DC in at the power board terminals, check the board's fuses for continuity, and check continuity through the thermal fuse/limit circuit. With the fridge on and calling for heat, the board should send 120V to the AC element in AC mode. The optical display gets its power through the ribbon cable, so reseat both ends. If it still won't work, our Tech Support service can walk through it with you. The 628661 is in stock, and so is the Nordic Cooling Unit 3381A for the N811. The N811 is discontinued, and Norcold's replacement is the Norcold N8X. See our Norcold replacement guide.
Since I can't confirm this 100% from here, please email us at info@rvfridgeguys.com or call 800-712-8822 with your model and serial number and we'll double-check it for you. You can also browse www.rvfridgeguys.com.
