Kenmore Upright Freezer Temperature Control Issue

Refrigerator & Freezer Repair
1

[SIZE=3][COLOR=#000000][FONT=Calibri]Hello,[/FONT][/COLOR][/SIZE]

[SIZE=3][COLOR=#000000][FONT=Calibri]I’m writing about an issue we are having with our Kenmore uprightfreezer model 253.9280213 purchased in 10/2000. We have noticed for some timethat while meat and even a bag of ice will stay frozen that ice cream wasalways too soft. We were perplexed but suspected some sort of temperaturecontrol problem. Also, occasionally water leaks out from underneath thefreezer. Not a log of water but enough to wet the floor nearby. I recentlybuilt a temperature data logger which stores temperature sensor data onto a micro-SDcard every minute. I put the logger into freezer for 24 hours. For comparisonsake I also took a 24 hour recording of our kitchen side-by-size freezer/refrigeratorthat seems to work fine. Attached is apicture showing the plot of the data. The suspect freezer shows temperature spikesat 12 hour intervals which I believe is due to the auto-defrost feature. Italso shows that the freezer never really gets as cold as the kitchen freezerand the auto-defrost keeps interrupting it’s attempt to get there. The temperature climbs 12 degrees during thedefrost cycle. The working freezer seems to cool down to the control band andthen bounce with that band, maintaining a target temperature, but the suspectfreezer doesn’t have this behavior. Do you think the problem is with having lowFreon, failure of the temperature control device or a failing compressor? Why would it leak water?[/FONT][/COLOR][/SIZE]

[SIZE=3][COLOR=#000000][FONT=Calibri]Thanks[/FONT][/COLOR][/SIZE]
Freezer Temp Data 013113.JPG (55.6 KB)

2

Here are your parts
Parts for Kenmore Freezer 2539280213 - AppliancePartsPros.com

Does the compressor run continuously except when the unit is in defrost?

Is the evaporator fan running?

To check for low freon remove the cover in the freezer and check the coils. The frost should be fairly even across the coil. If they only have frost in one area (usually where the freon enters the coils) then it is probably low freon.
Be sure that the unit has run several hours without a defrost. If you check them shortly after a defrost then you may come to the wrong conclusion.

Check the defrost thermostat. If it is deformed/bulged, replace it.
[COLOR=“Blue”]
Do you think the problem is with having lowFreon, failure of the temperature control device or a failing compressor? [/COLOR]
Cannot say without more troubleshooting.
I doubt it is the temperature control as the unit does seem to be trying to reach set point.

[COLOR=“Blue”]Why would it leak water?[/COLOR]
Check the drip tray to see if it is overfilling, the water is mots likely from the defrost.

Check the door seals.
It could be that they are leaking. This would cause a heavier than normal frosting up of the evaporator coils which could account for overfills in the drip tray. It would also cause the unit to have problems trying to reach set point temperature.

Take a 2 inch wide strip of paper. Place it between the door seal and the frame, then pull it out to see how the seal is. Work your way around the door.
Check the hinge side of the seal st see if the seal is grabbing as the door closes and is twisting. If it is a light coating of vaseline or white lithium grease should solve this.

Check that the freezer is level )front to back) or leaning slightly to the back.

Check the door’s bottom door hinges/cams/ramps. The door rides up and down on the ramps and is riding down when closed. This helps hold the door closed.

3

Thanks for the reply. Here is what I found:

[COLOR=blue]Does the compressor run continuously except when the unit is in defrost?[/COLOR]
Honestly, I’m not sure how to tell. The freezer makes an almost continuous humming noise but I think that is the air circulating.

[COLOR=blue]Is the evaporator fan running?[/COLOR]
[COLOR=black]Yes, the fan is running.[/COLOR]

[COLOR=blue]To check for low freon remove the cover in the freezer and check the coils. The frost should be fairly even across the coil.[/COLOR]
I checked about 1 hour before an expected defrost cycle. See attached picture. The frost was light but seemed to be heavier on the right and left ends than the fin area. Not greatly though. I did find about a 3/8" thick slab of ice on the interior floor just behind the removed panel.

Check the defrost thermostat. If it is deformed/bulged, replace it.
Where is this thermost located? I didn’t see any part that looked obviously deformed, but I could inspect the high res pictures again if I know where to look.

[COLOR=blue]Why would it leak water?[/COLOR]
Drip tray is bone dry at the moment. I found that water was leaking out of the door itself. Not sure if this was always the case, but it was this time. While I had the door open to remove the back panel I could hear something falling within the door itself. It sounded like ice falling within the door. Is that possible? Also, where is the drain to the drip tray? I couldn’t find it but then again maybe it’s under that slab of ice.

Check the door seals.
I don’t feel any cool air escaping from around the door, however I did the paper check anyway. The paper pulls out with some resistance, but not alot. How should it feel?

Check that the freezer is level )front to back) or leaning slightly to the back.
Found that the freezer is tilted slighty down towards the back.

Check the door’s bottom door hinges/cams/ramps. The door rides up and down on the ramps and is riding down when closed. This helps hold the door closed.
No issues there.

Thanks for the help!
Bill
Freezer Inside.JPG (52.7 KB)
Freezer Rear-Lower.JPG (37.6 KB)

4

[COLOR=“Blue”]
Does the compressor run continuously except when the unit is in defrost?
Honestly, I’m not sure how to tell. The freezer makes an almost continuous humming noise but I think that is the air circulating.[/COLOR]
Usually you can hear it also you should be able to feel it vibrating.
Since your graph shows the temperature always dropping after a defrost cycle, my guess is that it is always on.

[COLOR=“Blue”]To check for low freon remove the cover in the freezer and check the coils. The frost should be fairly even across the coil.
I checked about 1 hour before an expected defrost cycle. See attached picture. The frost was light but seemed to be heavier on the right and left ends than the fin area.[/COLOR]
Normally you would expect more frost on the tubing ends as there is less mass (the fins) to distribute the cold.

Not greatly though.
I did find about a 3/8" thick slab of ice on the interior floor just behind the removed panel.

[COLOR=“Blue”]Check the defrost thermostat. If it is deformed/bulged, replace it.
Where is this thermost located? I didn’t see any part that looked obviously deformed, but I could inspect the high res pictures again if I know where to look.[/COLOR]
It is the black device with a metal face clipped onto the top left of the evaporator coils.

[COLOR=“Blue”]Why would it leak water?
Drip tray is bone dry at the moment.[/COLOR]
Sounds like the drain is plugged

[COLOR=“Blue”]I found that water was leaking out of the door itself. Not sure if this was always the case, but it was this time. While I had the door open to remove the back panel I could hear something falling within the door itself. It sounded like ice falling within the door. Is that possible?[/COLOR]
Yes it is.
Most newer unit us styrofoam in the door as insulation. Older units use fiberglass. If there is a crack etc. in the door’s inner plastic panel warm moist air can get into the door. This then reduces the insulating efficiency so the problem gets worse. It would be a good idea to take the door apart and find out what is going on. Could be you are loosing a lot of your cooling through the door.

[COLOR=“Blue”] Also, where is the drain to the drip tray? I couldn’t find it but then again maybe it’s under that slab of ice.[/COLOR]
Often itb is directly under the evaporator coils. Does sound like it is plugged.

[COLOR=“Blue”]Check the door seals.
I don’t feel any cool air escaping from around the door, however I did the paper check anyway. The paper pulls out with some resistance, but not alot. How should it feel?[/COLOR]
This sounds OK

Just a note on your graph:
The second lower temperature is where the freezer should be re: 0 to 5 degrees F. It will be higher during and after a defrost cycle but should stay below freezing which it does.
I imagine that the first part of the graph is higher due to you opening the door.

Also the more food in the unit the less temperature variation you will see.

5

Update:
I finally got time to work on it again. I removed the defrost thermostat and inspected it for any outward appearance of damage. See picture attached. I didn’t see any signs of damage.

After reinstalling the defrost thermostat I cleaned out the ice in the bottom and cleaned out the drain hole. I then recorded another 24+hours worth of temperature data. The new graph is much different than the old (see attached). During the periods of time between defrost cycles the freezer seems to be controlling to a +5F to -5F deadband. During defrost cycles the temperature rises by 16F-17F. Where in the +5 to -5 deadband the defrost cycle hits will tell you how warm it will get. You can see two examples in the graph. Any thoughts on this performance?

Recall that this freezer is lightly filled. I might estimate only 15%-20%of the volume is being used. To test the freezer when better filled we wondered if bags of ice would simulated a filled freezer before taking a risk on real food. Thoughts on that?

Thanks
defrost thermostat.JPG (31.5 KB)
Freezer Data 0216013 rev A.JPG (22.1 KB)

6

Looks to me that it is doing a pretty good job.

Yes bags of ice will simulate a freezer with more food in it.

I am assuming that all monitoring is done with the evaporator cover in place.

7

Yes, I buttoned it all back up and let it run for about 8 hours before doing the last monitoring. Next, we’ll add a number of bags of ice, let it run for day, and then do another 24hr temperature recording to see if it’s more stable. Thanks for all your help!

8

Yes, I buttoned it all back up and let it run for about 8 hours before doing the last monitoring. Next, we’ll add a number of bags of ice, let it run for day, and then do another 24hr temperature recording to see if it’s more stable. Thanks for all your help!