Staff Answer
Sep 25, 2026 - 01:51 PM
If it runs on AC but won't switch to gas, the board may not be seeing the flame, or it may think gas isn't available. Make sure propane is on at the tank, and try lighting gas in manual gas mode to see if the burner lights and stays lit. Clean the burner and check the spark/sense electrode. If gas works in manual mode but the auto mode won't switch, the optical board or power board is the likely cause. The Optical Display Board 628974 has been discontinued by Norcold. The in-stock power boards are the 628661 and the Dinosaur 6212XX. See our Norcold error codes page. The N621 is discontinued, and Norcold's replacement is the Norcold N7X. 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.
