Unit working fine for 9+ years---staying cold even on low setting. For past month the freezer temp will get too warm & defrost everything, and fridge will get less cold. Even changing the rotary thermostat from 1 to 5 to 7---same process, freezer will stay properly frozen for a 3-4 days, fridge has correct temp---then 1-2 days of freezer defrost---then back to frozen again.

Fans are running (on and off cycle)---compressor running during proper freeze cycle---no odd noises. Cleaned condenser coils one week ago.

I am guessing main controller board failure not regulating temp on a daily basis...would you concur?
[control board looks to be a simple plug-n-play---any tricks to removal or reinstallation?]

Thanks,
Keith