Brand: Kenmore
Model Number: 253.28093801
Main Symptom: Evaporator freezing causing lack of airflow
What happens & when: Evaporator is freezing causing lack of airflow and warm temperatures.
Error Code (if any): None
Parts or tests already tried: Defrost thermostat and defrost heater have been tested
Photos / video link: None
My Father’s older Kenmore 253.28093801 (I believe manufactured by Frigidaire) upright freezer has recently been freezing the evaporator core thoroughly causing there to be a lack of airflow and cooling. He has been using this freezer since the summer of 2009, however in 2023 he moved and only started using the freezer again this past January 2026. For the last 2.5 years before he began using it this past January, the unit has been plugged in but with the digital control panel switched to “Off”. Last week he mentioned that it was not staying at 0 'F and was hovering in the 30’s even though the setpoint was still at 0 'F. I went over and found that the evaporator was frozen over thoroughly, however the evaporator fan was working.
Once the unit was cleared out and thawed, I tested the bi-metal defrost thermostat. I froze it in my freezer, and it has continuity when frozen, open when warm. I also tested continuity of the defrost heater assembly, and although it does not have continuity, I read that this could be because it has low resistance. I tested the resistance and it measures 38 ohms, which I searched and found to be more than adequate, unless my research is incorrect! I found the defrost drain to be plugged at the very top, it looks like a screw has been lodged in the drain for many years, possibly since the original assembly of the unit. I believe a clogged drain could lead to a frosting evaporator, but when I inspected the frozen evaporator it did not appear that the drain played a role at all.
This unit has a digital control and no manual defrost clock. Is there anything else i can check, or is it likely that the digital control/display is the most likely failure at this point?
Today I went by after the unit was defrosted to look at it further, which is when I discovered that the drain was clogged by a dropped screw. As you can see, 38.0 ohms was the resistance reading of the defrost heater. I have the defrost thermostat with me at home now, and after freezing it in my freezer, it shows continuity, and then when warming it with running water, continuity disappears.
I plugged in the freezer and the evaporator seems to get cold quickly enough, so as of right now, it seems as though the R134a refrigerant charge is OK. However when testing the defrost heater circuit, I got a reading of 40.6 volts AC. Does this seems appropriate? The compressor was running as the freezer had been unplugged for a few days and should not have been in defrost mode.
At this point I have not been able to find any other diagnostic information regarding this freezer nor any test sequences I can try with the control panel to “force” a defrost as some other refrigerators have, so I am asking for your advice about what to test next. Thanks!
