Hello all:

I got home yesterday to a fridge that wasn't keeping cold. Freezer seemed fine. Previously (last couple weeks) there has been excessive ice build up in the freezer section and an occasionally loud noise when the fan runs to cool the fridge, as if the fan was obstructed by frost/ice. Nothing was running when I got home. Thinking it was ice buildup, I ran a hair dryer into the fan vent in the freezer to melt whatever ice was on the coils. It did not work, but I did see what looked like foggy air coming out of the (return?) on the bottom of the freezer. In a last ditch effort, I unplugged the fridge, waited a few seconds, and plugged it back in. It worked, the fan kicked on (sans noise) and fridge cooled overnight. When I awoke this morning, the fridge was again not running but did feel cold. I unplugged, waited, and plugged in again, and the fridge kicked on. This morning, it's been cycling on and off just fine. I did not have a fridge thermometer, but I bought one to set in the fridge over the weekend to monitor. The temperature controls on the unit are set to 37 Fridge/0 freezer.

While that's a good thing that I have seemed to be able to mitigate this issue, I want to make sure nothing else might be wrong. I suspect something needs replaced, and reading through some things online last night I think it may be the control board. Do these symptoms square with that being the issue or should I be looking at the defrost thermostat or something else?
Any help you can offer would be excellent. Thanks!