Norcold Fault Codes SR or S (what they mean and what you need to do!)

Is Your Norcold Refrigerator Doing One of the Following?

• N400, N410, N412, N500, N510, N512, N621, N622, N821, N822
  • front display showing "S"
• N641, N642, NX641, NXA641, N841, N842, NX841, NXA841, 1200, 1210, 1211, 2117, 2118
  • front display showing "SR"

This fault code is indicating that there is a flame sense circuit failure. That circuit is on the rear power board and cannot be replaced. The typical issue here would be with that board and even the service manual will tell you to simply replace the power board, however, there could be another reason for this code!

We always tell our customers that before they replace the power board, they should try running it on clean DC voltage. This would mean that the coach is unplugged from shore power and that the inverter is not connected to your battery bank. If the same code appears with clean DC voltage, you then know that you need to replace the Norcold power board. If the code does not appear after eliminating your inverter, you most likely have something called "AC ripple" on your DC line. Simply put, it means that your inverter isn't filtering AC current like it's designed to and there are AC millivolts leaking over to the DC current that runs throughout the coach. The fix in this situation would be the inverter, NOT the refrigerator power board.

RECAP:

• Make sure you have clean DC voltage to the power board
• If the code remains, replace the power board.

Power boards can be found at the link below:

Norcold Power Boards

Your board should look like one of the two:

1. New style 628661 board (fits all models post 2006)

2. Older style boards (pre 2006).