Refrigerator is missing the thermistor

The friendliest place on the web for anyone with an RV or an interest in RVing!
If you have answers, please help by responding to the unanswered posts.

Oldlawnman

Member
Joined
Apr 28, 2024
Posts
21
Location
Myrtle Beach
Bought this used RV and realized fridge was too cold and hot ice in my beverages. Went to adjust the thermistor and the sticker to indicate how to adjust was there but no slider present and didn't see a wire either. What to do now? Thanks
 
Bought this used RV and realized fridge was too cold and hot ice in my beverages. Went to adjust the thermistor and the sticker to indicate how to adjust was there but no slider present and didn't see a wire either. What to do now? Thanks
... beverages had ice in them...
 
Bought this used RV and realized fridge was too cold and hot ice in my beverages. Went to adjust the thermistor and the sticker to indicate how to adjust was there but no slider present and didn't see a wire either. What to do now? Thanks
Some could have a non-stock thingy for an adjustment. Some of them are very small. Some are larger:

1714452985585.png
-Don- Auburn, CA
 
no slider present and didn't see a wire either
In order to give completely accurate answers we need to know the make and model of the refrigerator that you have. Based on what you have said I can tell you nearly all RV refrigerators that have thermistor temperature control are also designed to go into continuous cool mode if they detect a failed thermistor, either shorted or open. Removal of the thermistor would be seen as an open one and so the refrigerator will go to cooling all of the time and the result would be just what you are describing.
What to do now?
The first thing is to get us the make and model of the refrigerator so that we can look at the proper service manual to see what you need. You would then need to look on the main circuit board to see if the plug has not been removed. It sounds like a previous owner had a thermistor problem and just removed it and never got a new one. I have replaced several thermistors in various RV refrigerators over the years and also have disconnected the thermistor on more than one as part of troubleshooting the cooling unit.
 
Bought this used RV and realized fridge was too cold and hot ice in my beverages. Went to adjust the thermistor and the sticker to indicate how to adjust was there but no slider present and didn't see a wire either. What to do now? Thanks
Not sure this will help, but its a YOUTUBE Video on fixing a walk-in freezer not cooling. This guy I have gone to a few times for a fix. Do hope you can find something that will work for you.. Click Here "Restaurant Repairs" Good Luck!
 
Make and model would help us help you.
Absolutely. Dometic or Norcold? Zillions of different model numbers. Found on a sticker inside on the sidewall.

For EXAMPLE, a very common Dometic thermistor is this Dometic 3851210025 Thermistor Kit (this is a genuine Dometic product for $65 and comes with the plastic clips) or this aftermarket replacement Dometic 3851210025 Replacement RV Refrigerator Thermistor 12 Month Warranty but with no clips for $9.38.

Unplugging a thermistor is a way of testing the cooling unit, as it goes full cold if the thermistor circuit is open (unplugged)

Again on a Dometic, the thermistor plugs into the circuit board on the upper left side. The two pin connector in this pic.

3850712_1024x.gif


Norcolds are similar but different, so let us know what you have.

Charles
 
In order to give completely accurate answers we need to know the make and model of the refrigerator that you have. Based on what you have said I can tell you nearly all RV refrigerators that have thermistor temperature control are also designed to go into continuous cool mode if they detect a failed thermistor, either shorted or open. Removal of the thermistor would be seen as an open one and so the refrigerator will go to cooling all of the time and the result would be just what you are describing.

The first thing is to get us the make and model of the refrigerator so that we can look at the proper service manual to see what you need. You would then need to look on the main circuit board to see if the plug has not been removed. It sounds like a previous owner had a thermistor problem and just removed it and never got a new one. I have replaced several thermistors in various RV refrigerators over the years and also have disconnected the thermistor on more than one as part of troubleshooting the cooling unit.
 

Attachments

  • IMG_2689.jpeg
    IMG_2689.jpeg
    40.4 KB · Views: 3
  • IMG_2688.jpeg
    IMG_2688.jpeg
    82.6 KB · Views: 3
In order to give completely accurate answers we need to know the make and model of the refrigerator that you have. Based on what you have said I can tell you nearly all RV refrigerators that have thermistor temperature control are also designed to go into continuous cool mode if they detect a failed thermistor, either shorted or open. Removal of the thermistor would be seen as an open one and so the refrigerator will go to cooling all of the time and the result would be just what you are describing.

The first thing is to get us the make and model of the refrigerator so that we can look at the proper service manual to see what you need. You would then need to look on the main circuit board to see if the plug has not been removed. It sounds like a previous owner had a thermistor problem and just removed it and never got a new one. I have replaced several thermistors in various RV refrigerators over the years and also have disconnected the thermistor on more than one as part of troubleshooting the cooling unit.
 

Attachments

  • IMG_2689.jpeg
    IMG_2689.jpeg
    40.4 KB · Views: 7
  • IMG_2688.jpeg
    IMG_2688.jpeg
    82.6 KB · Views: 7
Is the thermistor completely missing? It should be clipped to the cooling fins. Moving it up or down adjusts the temp. If it is gone, the refrig will go into continuous cooling.
 
Dometic RM 2652 will take one of the thermistors I listed above in post #7.

Find the hole in the back wall just below the cooling fins and push a string thru. Use the string to pull the thermistor thru and secure it with wire ties and seal the hole with a little putty.

Charles
 
Take a look at the back of the refrigerator. Is it still an evaporative cooler?

I recently converted mine over to a JC Refrigeration dual compressor cooling unit. It has no thermistor.
 
So how does it control the interior temperature?

It has a pair of thermostat controls built into the system. The refrigerator sensor is hidden but the freezer one is clipped on the bottom of the shelf. The refrigerator and freezer operate independently.

This picture was taken 30 minutes after powering the cooling unit up. The second picture was 30 minutes after that. No more waiting 12-24 hours for a cold refer!
 

Attachments

  • Image.jpeg
    Image.jpeg
    61.6 KB · Views: 3
  • Image-1.jpeg
    Image-1.jpeg
    55.1 KB · Views: 3
Dometic RM 2652 will take one of the thermistors I listed above in post #7.

Find the hole in the back wall just below the cooling fins and push a string thru. Use the string to pull the thermistor thru and secure it with wire ties and seal the hole with a little putty.

Charles
Supposing I need to be checking the back part of the refrigerator from the outside to check check for possible clues to why it might
In your picture it looks like a wire coming out of the back below cooling fins, or is that something else I am seeing?
 

Attachments

  • IMG_2694.jpeg
    IMG_2694.jpeg
    74.9 KB · Views: 7

Latest posts

Members online

Forum statistics

Threads
132,714
Posts
1,399,622
Members
138,350
Latest member
afshan
Back
Top Bottom