Maytag Refrigerator too Warm

[TechnicianBrian]

Model #MFI2568AES, this bottom mount refrigerator, with the freezer drawer on the bottom, was cooling properly down below, but the fresh food section was to warm for food. This is usually an indication of an evaporator fan failing, or possibly a defrost issue, but I needed to do a bit more to get to the bottom of this problem.



This particular unit is part of the Ice2O line which gives the space benefit of a french door above, while still having ice and water available from a door dispenser. Because the freezer is in the drawer, a small ice maker section was placed in the upper left corner in the top section and cold air is blown by the evaporator fan from the freezer directly to this ice maker section. The cold air is moved by another fan into the fresh food section where it can cool things down as it finds it's way back to the freezer. Looking like a fan issue, I set off to figure out which one was the problem.

After verifying the evaporator fan was functioning (I opened the drawer and heard it running) I pulled the ice maker from the housing to take a look at the ice fan. Because it is mounted to the ice maker, it helps during the ice production process while also providing cool air movement into the fresh food section. With the unit in my hand, and still connected to the wiring harness, I found the fan motor rotating very slowly. Much less than expected, and not nearly enough to actually move any air.

Often, fans used in refrigerators are basic 120vac fans with two wires and they either run or they don't. This unit uses 12vdc fans for air movement allowing the control board to speed up or slow down the air movement depending on cooling demands. These fans have 3 wires that run to them. The first is a constant 12vdc source that is always present. The second is a reference ground back to the board. And the third is a pulsed voltage from the board. Do not measure these voltages in reference to the chassis as you will not get correct readings. How the board controls the voltage is by changing the pulsed voltage to the motor. The small control board inside the motor will interpret this signal and change speeds accordingly.

To test these motors, I removed the fan connector and checked for the source and signal voltages from the control board. You cannot check the resistance of these motors because each wire does not connect to a motor winding directly. Finding only 7.8vdc on the first wire, and 1.7vdc on the signal wire told me the control board was bad. I also checked the voltages at the control board (it's on the back) just to be certain. Finding the same reading at the board, it was time to install a new control board into this refrigerator. With a new board installed, both fans operated as expected, and the refrigerator was once again cool.

Just a note: if you replace the board on one of these units, there part should come with a set of instructions to program the board for operation. Simply replacing the board will not allow the unit to function unless it is programed. Be sure and follow directions and you should be just fine.

[consumer]

Hi,

Want to replace it... I came across an online stores - stores San Francisco where we can by and sell all brands of refrigerators.