Whirlpool_Refrigerator_WRT3L9SZY Slight Icing on front of Back Wall and running to much

[N11778]

Replaced the Evaporator fan it was RUNNING at about 1/10 the speed of the new one.  All is now well.

It's a brush-less electronic 120v 60cps motor,  the motor control board built into it must have been the problem it turned OK.

The frig and top freezer where staying cold but it was running a lot more than it should have about 80% instead of 50%.

I hope this helps someone else, most of the searches tell you to change the defrost board .

This defrost board has a cool test to see if its working it was hidden in the Service paperwork stuck inside the back of the frig.

To test the defrost you turn off the power for at least 30 sec, turn the inside temp to OFF Plug it back in and it will defrost.

Should defrost for about 20 min then stop, you can hear the defrost relay click on and off.  I used a KiloWatt to monitor the current

Current should be 400 watts during defrost and about 130 Watts Running.

[Vance R]

From your description you have a defrost issue. Inspect the evaportor frost buildup. The heater resistance is spec at 42 to 30 ohms. The bi-metal should be zero ohm at 15 to 20 deg f. You can do a manual defrost with a steamer to get things working for awhile and get access to connections to make tests.