In many cases the problem is do to the fact that the evaporator fan cannot operate freely due to an ice.
Walk in freezer evaporator fan not working.
Also check all gauges to be sure temperatures subcooling superheat and pressures are all normal.
This was a walk in cooler that had been down for a few days.
If the door switch is activated but the evaporator fan motor won t run replace the evaporator fan motor.
If the evaporator fan motor is not working the freezer will not cool.
Check fan motor and its electrical circuit.
If the freezer isn t working you should be able to tell quickly.
System overcharged with refrigerant.
Repair and add charge.
If the evaporator fan motor stops working your freezer will begin to defrost.
Next check for a clean coil and clear drain line.
Leaks and other issues in the shell can cause too much moisture to get in which can cause a bigger issue.
Open the freezer door and feel for cool air with your hand.
To check the evaporator fan motor open the freezer door and then manually activate the freezer door switch.
If the fan is not running unplug the refrigerator and remove the evaporator fan cover.
The meter should read near 0 ohms.
Insufficient refrigerant in system.
The evaporator coils are usually located behind the freezer compartment and the evaporator fan should be right in front of them although it may be offset to one side or the other.
Next check for continuity through the light blue wire in the same way.
On most refrigerators the fan motor will not run when the door is open.
Cooler is freezing if the walk in cooler is freezing up the first step is to melt ice off the evaporator and then check that the evaporation fan is running and rotating correctly.
Clean walk in cooler and walk in freezer condenser coils.
If it doesn t the refrigerator won t get cool enough to preserve your food.
Drop down the back freezer panel and unplug the evaporator fan.
The door will be a main part of the cooler.
I found several issues with the unit the unit had a bad contactor compressor txv ect.
To check for continuity put the meter leads on either end of the red wire with the white stripe one on the evaporator fan plug and the other on the control board plug.
The freezer or cooler shell need to be regularly inspected for loose panels or installation and leaks.