No worries about "answer tag" and not being able to get back to me for a while. I understand we all can get busy.
To answer your question, yes. You would have definitely needed to defrost the evaporator coils
that were frozen over either before or immediately after replacing the board. If you hadn't the evaporator since so frozen over will choke off all the cool air flow to the ref cabinet and cause it to warm up.
So I advise unplugging the machine as soon as possible. Removing the food from the freezer and removing the screws to the back evaporator cover from inside the freezer section. This will expose the evaporator coils so you can defrost them yourself with a hair dryer. Just fan the hair dryer back and forth a out six inches away from ice. It should take about 30 mins for it to completely defrost. Also put some towels down on the inside of the freezer floor to catch and soak up the water that will come from defrosting the ice.
After the ice is defrosted close everything back up and plug the machine in again and set freezer for about 0 degrees and ref to about 37 degrees. Let it run and you should be ok.
Now if you don't want to go through that much trouble just to defrost the evaporator coils I would suggest removing all perishable food and putting it in another ref if you have it or coolers and unplug the machine for 3 days. This will totally defrost the evap and the inner water lines. But realize you will not have use of you ref for three days.
So if you can't go without your ref for that time period or don't have alternative means to cool your food do option one.
If the evap coils are not properly defrosted your problem will never totally be solved. As you are finding out.
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