FIXED Kenmore Elite 596.76254701 Bottom Freezer - freezer getting too warm...or is it?

[BobzYourUncle]

Model Number

596.76254701

Brand

Sears Kenmore

Age

More than 10 years

We have a 13 year old Kenmore Elite refrigerator/freezer with a single top door and a drawer-type bottom freezer.

The unit's motor start device recently died and we lost a lot of food, so I installed a refrigerator/freezer alarm (link). For a few days, everything seemed to going just fine and the freezer was staying near zero degrees (F). The the temp started climbing over several days, so I turned the temp setting down twice, until I reached the minimum setting of 1, and still couldn't get the freezer to stabilize near zero. Meanwhile the refrigerator temp stayed between 34 and 44 degrees. The freezer finally tripped the alarm at 15 degrees, so we pulled all the food out of it and moved it to another freezer. The freezer was about 25% full at that point.

Yesterday I pulled the back panel out of the freeze section and verified that the evaporator coils were not icing up and that the circulating fan is working. After I put it back together, I returned the freezer temp control to 3 (which I think is the factory setting), and it's been acting better. Temps are staying near 0, but this afternoon it climbed up to 16 degrees for a short period and again tripped the alarm. I assume that was a result of the defrost cycle, but for the air temp in the (almost empty) freezer section to go that high seems wrong. The only change that I made was to remove the ice maker, which we've never used.

My question is, could a 16 degree temp rise be normal? Right now, I don't trust the freezer enough to put anything other than ice cubes in it.

Thanks!

 

[Jake]

When the temperatures rise like that is the evaporator and condenser fan motors, and compressor running? Or is the refrigerator dead silent?

Also, if its dead silent, see if you can time how long it stays dead silent until the compressor kicks on again, should be about 20-40 minutes.

Jake

 

[BobzYourUncle]

Jake, thanks for the reply!

I had to wait over 24 hours for it to repeat. The temp went up to 15 degrees and stayed there about 10 minutes, then went back down to normal. The fans were running the whole time. I think the compressor was also running, but it's hard to tell because it's so quiet. I assume that it was going through the defrost cycle and nothing was wrong. The temp sensor is laying on the top shelf and air flow from the fan goes right across it. I imagine that if the freeze were full of food, the temperature won't go as high as it will with an empty freezer compartment. Does that sound right?

Do these units defrost on a regular interval, or are they smart enough to only defrost when necessary? It looks like the defrost thermostat (W10165425/WPW10165425) is there to prevent the defrost element from coming on if the freezer is too warm.

Another thing that puzzles me: How does warm air from the refrigerator return to freezer section? I see the duct, right above the evaporator fan, that routes cold air up to the refrigerator section, but it's not obvious how air returns.

Thanks!

 

[Jake]

I imagine that if the freeze were full of food, the temperature won't go as high as it will with an empty freezer compartment. Does that sound right?

Bingo! I wasn't aware you didn't have anything in the freezer at all, now it makes sense.

Do these units defrost on a regular interval, or are they smart enough to only defrost when necessary? It looks like the defrost thermostat (W10165425/WPW10165425) is there to prevent the defrost element from coming on if the freezer is too warm.

Your model uses adaptive defrost control, meaning no defrost timer.

Here's the JAZZ control board for your model that uses adaptive defrost control:
WPW10503278 Electronic Control Board


Here's the defrost thermostat for your model, it clips on the top of the evaporator coil:
WPW10165425 Bimetl-Def


If its not frosty, you will have to put it in a glass of ice water for at least 5 MINUTES before ohm testing it, watch this video:

Another thing that puzzles me: How does warm air from the refrigerator return to freezer section? I see the duct, right above the evaporator fan, that routes cold air up to the refrigerator section, but it's not obvious how air returns.

There is a return air duct in the freezer too, its located at the very left side of the freezer evaporator coil metal mounting bracket.

Jake

 

[BobzYourUncle]

It sounds like everything is functioning as it should.

Thanks again!

 

[Jake]

Glad to help!

Jake