coils are clean. temperatures are fine in both sides. freezer fan will no shut off and not cycle. please help. very handy, builder, etc.
If it’s running and cooling ok you are probably ok That frig I bet has an 80% run time or better so unless a guy is sitting there 24-7 and documenting the times it’s hard to determine that it is always running and never shutting off it may be shutting off when your not around I wouldn’t worry to much about it until it quits cooling
yes, we have sat in front and waited. the fan used to cycle once in awhile, now it is on 24/7. will it burn it out and/or waste electricity? thank you
The freezer fan MUST turn off during defrost cycle, if not it would bring the freezer temperature so high all the food would start to thaw out.
You may have refrigeration problems, measure the back wall freezer temperature and post.
Compressor comes on along with the evaporator motor ("A" coil in your example). When thermostat is satisfied, compressor cycles of and after 120 seconds so does the evaporator motor.
When the ADC (Adoptive Defrost Control) senses that the unit needs defrosting the compressor,condenser fan motor (outside unit on central air), and evaporator motor ("A" coil or furnace motor) turn off, and defrost heater energizes. After a predetermined time, the unit comes out of defrost and the compressor and condenser fan energize. The evaporator fan does not until the coil temperature reaches the defrost limit/fan delay setting (usually 25* F.).
The evaporator now becomes energized.
Since this is determined by the ADC, if there is a problem with this control you will have problems with said components.
The ADC replaced the conventional timer as it was felt to be more energy saving (defrosting only when needed), however there seems to be many bugs in this system. There is an excellent book available called the "Fridge Doctor", even and old retired HVAC/R Teacher learned from it. 
you have been most helpful in making me understand the workings. the temperatures seem to be ok, but it might be a little warmer than usual. if the defrost cycle were stuck on, the frozen foods would not be frozen anymore, but they are. the compressor seems to be cycling properly, ice being made, etc. it is just the evap fan stuck on. i really do not wish to buy an entire control board to repair this. is it ok to just let it run and not fix it? i have a/c motors in my pellet stove, and one that circulates the warm air into the room from the exchanger runs the whole time the stove is on, for many years. thanks, Michael from Precision Remodelers
It’s like I said early on you might be chasing after something that isn’t broke Worry about it when it stops cooling.
Yes, Dan. Thanks for doing that. There is a delay in getting rid of the duplicate posts but it is being done.
I have the same problem with a GE Profile top-freezer fridge. I replaced the fan after it started a lot noise. (Later I discovered that lubricating the shaft and checking the grommet would have sufficed). The original fan in the breakout diagram on the GE site doesn’t have a sensor. The new one does. After replacing it keeps running non-stop. Previously it used to turn off regularly. I am curious to know what happened in your case? Did you manage to solve the problem?