Converter Not Charging Battery

Confirm that the main fuses in the 12V distribution panel are good, and that the charger ac circuit breaker is closed. Then try disconnecting the battery and solar system entirely and see if your 12V loads will run directly on the WFCO. That won't hurt anything. If they do then your charger is working, if not then it has failed. In that case, I agree with Motor7 re Progressive Dynamics as a replacement. 

While on shore power, set the fridge to DC (battery mode)...set it for the coldest setting.

Within a minute (or as little as a couple of seconds) the converter fan should activate letting you know the charger is operating. If, after say, 20 minutes, the fan has not come on, and your battery monitor lights are showing less than full, it's certainly time to investigate further.

There is also a test done by Dave Hickey who attended the Kentucky MiniMini last October. He found that it was not necessarily vibration, but the screws for the grounding (marked FG) not being tight. Since the current that should be going through the FG screws cant, it then goes through other parts including the bridge rectifier which manifests as a cold solder joint on the negative terminal. Dave Hickey repaired a couple of bad ones while we were at the Kenucky MiniMini. We had a brand new one in the box that he used to take pictures for the guide he posted on the Facebook group last October:

WFCO 89xx Converter Field Repair Guide. Created by Dave Hickey.

In essence, one needs to check the underside of the converter's circuit board after disassembling to move shields out of the way and then looking at the rectifier solder points. If one looks burned, it is the problem one and needs to be cleaned up and re-soldered.

Of course, if the converter is still under warranty, don't do this. However, if it is out of warranty, it would be a lot less expensive than buying a new converter if it is able to be repaired. It wouldn't hurt to try.