[Gene]

Does the fan in the freezer work?

Gene.

[tfrink]

yes, the fan works. i manually defrosted the coils, and can feel the air going in to the fridge now. but they were completely iced over. i figure it is probably one of the 2 things you mentioned, but was hoping it might magically fix itself after i moved the box that wound up on top of the output vent.

[phillb]

[FONT='Verdana','sans-serif']Same problem - cold freezer, warm refrigerator. I've replaced the damper assembly and the thermostat. I don't see any ice buildup on the coils or in the freezer. Compressor coils ar fairly clean. I can get the refrigerator plenty cold enough if I detach the control panel from the ceiling and let it hang down. This removes the damper, which seems to be working, from the airflow from the freezer. This is the only way I can get the refrigerator cool enough. If I reattach the control panel, the refrigerator warms up to about 40-45F and the freezer to about 20F. The compressor seem to be able to get things very cold, but I’m not sure it cycles properly even though I’ve replaced the thermostat. Also, I cannot locate the air return duct to check it. Thanks.[/font]

[Gene]

Hello,

Your refrigerator has some differences in the controls design compare to most other refrigerators. It's explained more detailed in the attached file.

When you replaced the thermostat which controls temperature in the FREEZER it is very important to place the capillary tube in it's holder on the damper control.

I also attached the instructions on the damper control testing and replacement. Hopefully it will help you to fix it.

Here are the breakdown diagrams and Parts for Maytag MTB2156DEW Refrigerator - AppliancePartsPros.com

Gene.

[sabre66]

Hi, Thanks for the great thread, just too long to read it all though.

I most certainly have a defrost issue, trying to determine what is the cause.

1. This unit has no defrost timer, so am told it is controlled by Def control module WR55x10900. Can you tell me how to test this module (with multi meter) and what readings should be?

2. For the Def heater - WR51X10038, I would check that as well. Could you give the same advice on testing this?

3. Def T-stat -- i changed this before, but now not sure i got the right one. i used WR50X10071. But there are two similar looking items (620 on diagram) - are they supposed to be the same unit? which one is the ..71 vs ..73. Any way to test?

Thanks for any help you can give.

[Gene]

Originally Posted by sabre66

...I most certainly have a defrost issue, trying to determine what is the cause...

Hi,

Why do you think so? What is the condition of the evaporator coils?

There is something missing in the model number you posted. Verify and repost it please.

Gene.

[sabre66]

Originally Posted by Gene

Hi,

Why do you think so? What is the condition of the evaporator coils?

There is something missing in the model number you posted. Verify and repost it please.

Gene.

Hi Gene, try model number GTH18EBT2RWW. Every two weeks or so the fridge gets warm and then the compressor starts to run longer. I have been taking off the back and manually defrosting, as the coils always have a lot of frost on them after the two weeks. The coils have a lot of frost on them, but look fine when cleared off. The fridge may have gotten some extra voltage during hurricane Sandy, and I have replaced both fan motors so far. It is getting a bit tiresome manually defrosting each week, so this is my last chance to fix or get a new one. Thanks

[Gene]

Thank you, this model number works. You are on the right track with diagnostic. There are four parts in the defrost system in your refrigerator. They are: the Adaptive Defrost control board, the defrost heater and two defrost thermostats connected in series.

Start the troubleshooting from checking the defrost heater and the defrost thermostats for continuity. You can do it from the ADC control board by checking for continuity between the wires connected to the terminals DF & L2. It should read between 20 Ohms to 40 Ohms.

If the reading is incorrect, check for continuity the defrost heater and each of the defrost thermostat separate. Both defrost thermostats must be ice cold at this time.

If the reading is correct try to force the defrost manually as described in the attached file.

- The ADC control board Part number: WR55X10900

- The defrost heater Part number: WR51X10038

- The defrost thermostat Part number: WR50X10073

Gene.

[sabre66]

Gene. This is fantastic. I am going to work in it the next few hours.

Thanks

Tim

[sabre66]

OK. Open the top to the. ADC board and did the test and got 36 ohms. So that sounds good. But when in there saw black on the top and side. Looking closer seems to be from capacitor?? MOV1, the blue cap there. See cracks on the side and some black residue. Think that would be the issue and need to replace the board?