Any Refrigerator Experts out there?

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I have a Maytag french door bottom mount freezer (MFF2557HES) that is causing some trouble. The freezer cools as it should down to -1°F but I'm having a hard time getting the fresh food section to hold 37°F.

When going through the diagnostics everything tests out as it should, including the damper door in the FF section. The issue I think I have is the damper door opens when the unit starts to run, then I close the doors to allow it to cool and I think the damper door closes shortly after that. The FF never sees enough cold air from the freezer to achieve the proper temperature. The freezer is frosting up a bit at the bottom of the evaporator coils, but nothing too extreme. For now, I've propped the damper partially open to allow the FF section to cool so my food won't go bad. It's hanging around 35°F for the time being, so that tells me that the thermistor in the FF part is functioning.

With everything passing the diagnostic tests, might this be a bad control board? I could go with my current workaround, but I don't want to be babysitting it through the summer. I'm open for ideas, and will try to add new info when requested.

Jamie
 
Might not be the issue, but a good easy place to start is to use a brush to clean the dust from the condenser coils underneath. That should be step 1.
 
What Rolla07 said...IN the HVAC schools/ref section, clean coils underneath your fridge, where the compressor is and the coil fan is located...dust and lint clog up coils and the refrigeration process is reduced. Dirt is a killer on coils, always look for dirt or lint , you can vacuum it off easily..
 
Sorry, I should have had that in the OP. I clean the underside of it twice a year, spring and fall, because it's in the garage. It fills up with leaves easily.

With my workaround it's holding a steady 35°F at this point, and the freezer is slowly defrosting. Unless an expert says otherwise, I'm still leaning heavily at the board being bad.
 
I am a 30 year Maytag tech. First check air flow. If evap is iceed up that's your problem. Remove evap cover check for blockage. Check upper left corner. If all clear check frost pattern evap should be frosty from bottom to top. Very common for this model to have a low performance compressor. If all is fine check evap motor could be slowing down. Next it could be damper motor or thermistor that is mounted in control panel. Good luck. Thermistor controls damper through control.
 
Originally Posted By: Badoil
I am a 30 year Maytag tech. (snip) Next it could be damper motor or thermistor that is mounted in control panel. Good luck. Thermistor controls damper through control.


BITOG never fails! I was hoping that someone would be able to tell me that something other than the control board was the underlying issue. I will get access to the thermistor in the upper panel of the fridge and see what I can do to test it. The damper motor does operate, although is does make a slight grinding noise. It does open and close when commanded through diagnostics.
 
Originally Posted By: threeputtpar
The damper motor does operate, although is does make a slight grinding noise. It does open and close when commanded through diagnostics.


Could be the damper motor and/or controls for the damper isn't positioning it correctly. You've manually positioned the damper to give the correct temperature, so seems the rest of the systems seem to be operating well enough to give the fresh food compartment the correct temperature once the damper is positioned manually.

Is the control system for this damper either open or closed, or is the damper controlled to be someplace between open and closed (ie, a proportion control system) based on the fresh foot thermostat setting?
 
My damper is either open or closed, it never stops in the middle anywhere.

Somehow, the damper is being commanded by the control board to open all the way when the evaporator fan starts. Only a few seconds after the damper opens completely it closes right back up again, yet the evaporator fan continues to run. To me it seems that everything in the system is operational except possibly the fresh food thermistor and/or the control board. I don't want to shotgun this repair, so I need to do a bit more with the multimeter.
 
Thermistor at 70 degrees should be 10'000 ohms at 36 degrees should be 29'500 hope this helps
 
Originally Posted By: threeputtpar
My damper is either open or closed, it never stops in the middle anywhere.

Somehow, the damper is being commanded by the control board to open all the way when the evaporator fan starts. Only a few seconds after the damper opens completely it closes right back up again, yet the evaporator fan continues to run. To me it seems that everything in the system is operational except possibly the fresh food thermistor and/or the control board. I don't want to shotgun this repair, so I need to do a bit more with the multimeter.


I had a Frigidaire that used the fully open or fully closed fresh food damper door logic. The basic operation was when the FF thermostat called for cooling, the door opened all the way and cold air from the freezer compartment was flowed in. When the thermostat said the FF compartment was cold it closed the damper. My damper stopped working and the fix was a new FF comparyment thermostat. Your damper control is definately messed up for some reason, as it should stay open until the FF thermostat says it's cold enough per the temp setting, then the damper should fully close until the FF compartment warms up again.

What's the damper do if you set the FF thermostat setting all the way to the coldest setting? If it doesn't stay all the way open for a very long time then something in the controller is messed up.
 
On full cold setting for the FF section, the dance the damper does is the same. It is cold enough here in WI again that it's harder to diagnose because this is a garage fridge and it's getting down to single digit temps overnight.

I will keep tinkering with it and get to testing the resistance in the thermistor. Hope it's easy as replacing that and not the board.
 
UPDATE: I've tested both thermistors, and the freezer one was around 86,000 ohms at 0°F and the fresh food one was 31,500 at 35°F. Both working properly. I think that I've reached the conclusion that I was hoping I would not, that the control board is malfunctioning and closing the damper door too soon.

Thank you everyone for the help and suggestions.
 
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