Samsung RF263BEAESR Fridge is too cold, thermostat reads 15* too high

First time working on a fridge so bear with me, I’m having trouble figuring out why this fridge seems to be over cooling.

Basically when you press the “fridge” button, it displays the target temperature (44*) however when the fridge is actually 26*-30* (per 2 different digital thermometers, infrared and instant read food thermometer). This is causing the water in the water filtration system to freeze and our food to freeze even when on the highest temp setting (44*).

I took it apart. I found 3 thermistors. One is on the defrost heater. Then there is another at the very top of the fridge on the back panel. The 3rd is near the actuator for the CoolSelect Pantry. I checked the thermistor at the top of the back panel and it reads approx 12.6K Ohms when put in ice water, same story with the thermistor in the Cool Select Pantry. They return to approx 5k ohms when at room temperature.

I would tend to think these are what determine when the compressor runs and thus cools down the evaporator coils. Its not an issue I dont think with a stuck relay for the compressor as it does cycle on and off but seems to think the fridge section is warmer than it is. The freezer portion is perfect, temp wise.

Anyone know how this thing determines the current fridge temp? Does it use a combination reading of these sensors I tested today? If these test at the correct resistance readings, does that indicate a problem with the mainboard?

Here is how I was testing the 2 sensors I found:

Here is how far I’ve disassembled it at the moment in case there is some additional troubleshooting I can do.

I also pulled the back panel where the circuit boards are and reseated all the connections for good measure. Checked for burn marks on the board, did not find anything. Also, here are the 3 back boards, cover removed: Top one seems to have a larger chip on the backside which is probably where most of the logic is I’m guessing, most of the connectors are there.

Sounds like a control board problem.

Here are your parts
Parts for Samsung RF263BEAESR/AA-0000 / Refrigerator - AppliancePartsPros.com

Here is a link to a service manual although it is for a RF256 much of how they do things should be similar.
You will have to join the site and be logged in to be able to download it.
http://appliancejunk.com/forums/index.php?action=downloads;sa=downfile&id=436;t=1450089730

Here is a tech sheet. it is for a RF263T so again not an exact match but should be close.

[quote=denman;894783]Sounds like a control board problem.

Here are your parts
Parts for Samsung RF263BEAESR/AA-0000 / Refrigerator - AppliancePartsPros.com

Here is a link to a service manual although it is for a RF256 much of how they do things should be similar.
You will have to join the site and be logged in to be able to download it.
http://appliancejunk.com/forums/index.php?action=downloads;sa=downfile&id=436;t=1450089730

Here is a tech sheet. it is for a RF263T so again not an exact match but should be close.[/quote]

Thanks denman for the reply. I have some updates.

So I replaced the control board, and the problem remained. I then replaced 2 of the 3 thermistors because they are like 6 bucks a piece. The third is not available locally however I swapped one of the one of the ones I replaced to the 3rd spot as it uses the same connection, no change, fridge is still running at 25-27*, still well below freezing .

I also tested all 3 thermistors in ice water and they read 12.5k ohms or so and a little over 5.5k ohms or so at room temperature. Obviously have several spare thermistors for spare parts at this point I guess.

Here is the front panel right now in regards to temperatures:

I have 2 thermometers in the unit right now, one on the bottom right right is in the freezer and another is in the fridge. The freezer jumps up a bit when opened but then cools down to -5*, exactly what the set point is on the panel. It is working perfectly. I’ve bumped it up to +3* as well and it stays there like it should. Here are the current temps:

I checked the damper/ at the bottom for the CoolSelect Pantry and it seems to remain in the closed position at all the times I checked it, thus blocking airflow from the freezer compartment.

There is another opening which I assume goes to the freezer section behind the foam/plastic panel where the fridge evaporator is. I’m not sure what that is for.

I’m thinking perhaps the control board was DOA but I really doubt that, I guess its not entirely impossible, not sure if Samsung uses refurbished parts so maybe this one was DOA with the same problem?

Otherwise I’m wondering if perhaps an issue with the power supply board perhaps which fried the replacement control board? If you look at the pic in the first post, the power comes into a small board in the middle then that goes to a larger board with some large capacitors at the bottom, then from there it looks like power gets fed to the control board. I have a multimeter I can use to test various wires if that would be helpful. I put it into diagnostics mode where it flashes 8 8 or what not but didn’t see anything flash like I’ve read it would. I think the fridge itself thinks it is still working as it should.

I have another control board on order which will arrive Monday but am a little scared to pop it in if say I have a bad power supply board which would then fry the 2nd replacement control board.

Any other troubleshooting ideas are welcome, I’m open to anything.

Yes it would be a good idea to check the power supply.
If I am correct it should have 2 DC voltages coming out of it.
Neutral/common is black.
+5 volts DC is red
+12 volts DC is yellow

Check that the voltage is OK.
Also check them for AC voltage which should be low.

There is one thing that I recommend with and electronic fridge and that is that you run it off an appliance surge protector. A 1000 joule unit is preferred but a 750 will normally do the job.
It just plugs into the wall receptacle and then you plug into it.
They are available at Home Depot etc.
It should stop voltage spikes on the line from screwing up the electronics.

Where you able to fix the issue with your fridge? I am experiencing the same problem and I am at a lost on what to do. Your response is greatly appreciated.

Defrosted fridge cause it was frozen over and fan was making a bad sound
Now fridge is freezing our food solid.
Ordered temperature sensor and defrost sensor - will give it a go and update.

Hi sseiyah,

Were you able to figure out the problem? I am having the exact same problem with this model fridge so would really like to hear the root cause if you got it working

Cheers,

Typo

Anyone fix this? I am having the same issue with an RF4287HARS.

Mine came to be not working, but with a brand new control board. Turns out one of the wires on the harness was in the wrong spot, due to a revision of the board, or something else. So I moved the wire, and the fridge/freezer was working amazing.

Freezer is sitting at 0 degrees (confirmed). This unit has that flex drawer in between the fridge and freezer, and it is sitting at 37 degrees (confirmed) and thats where its set.

Fridge is set at 46, as high as it will go. Confirmed temp is 25-30. Its freezing the milk its so cold.

I havent taken mine apart yet, but I plan to start testing tonight. I want to test the resistance of the thermisters, but I plan to do it back at the control board. The other thing I want to do is make sure everything else is wired correctly.

One other thing…the service manual has a procedure for temp correction. Im not 100% clear if it changes the temperature that the fridge actually goes to…or if its just a correction factor so if you KNOW the fridge is 30 degrees, the display will show 30 degrees.

My last resort is to buy a new control board, but try to find one with the exact numbers/revision that my unit calls for.

Justin

I’m having the same issue with samsung rf263beaesr/aa and I’ve downloaded the service manual for it and found that a sensor is reading about 0 volts and should be between 1.2 and 5. The sensors says 5:Icemaker-Sensor on next to last page and you check it on the computer board at check points 1-7. I tried to unplug the ice maker auger and this lets is go up to 5 volts and check the resistance on the thermister and it’s about 10k. Then I thought maybe it’s shorted out to the motor and took it all apart and it wasn’t. I’m still leary of replacing the auger assy but might try it. I also try to leave the ice maker plug and it complained defroster bad or something like that. I did noticed some talk about updated ice maker parts and even a different computer board too.

like the auger Part Number DA97-12540G (AP6025062) replaces PS11758619, DA97-12540A.

I was having the same issue with a samsung fridge.The problem was a faulty main board.Thanks https://ilektroepiskevi.gr/

FIXED the overcooling: After spending so much money I fixed it myself:
Short Story:

  1. Found my Samsung model + version
  2. Found 2 temperature sensors for my model (RF263BEAESR/AA version 2)
    DA32-10104N
    DA32-00011C
  3. Changed the above sensors
  4. DONE
    PS, Start with small steps:
    Make sure your panel temperature set to a higher temperature and it is not to Power Freeze
    If you have an extra freezer/fridge, then move your food to those and unplug this fridge for 72 hours
    Now if it still freezes your food, it is time to do some repair:
    a) Change the above temperature sensors (according to your model)
    b) If that does not work change Mainboard
    c) and if that doesn’t fix it, then if you think the display panel does not work, you can change that
    Good luck

Long Story:
I asked a technician (with a high review) to come and fix this overcooling:
He came, charged my $80 for service call and said the solution is to come next time bring two parts: Mainboard and Display Panel, change all and it will fix it!!
The suggested solution would have cost me $400 for part + $200 labor - $80 (waiving the service charge)!
Then I decided to do what he suggested but to do it myself
I changed the mainboard: it did not fix the overcooling
Then I was desperate and also changed the display panel and that also did not solve the issue
Then I realized that the temperature difference between the temperature that the display panel shows (not the set temperature) and the inside temperature (measured with a thermometer). The temperature difference was more than 8 C
I looked through the repair pdf for the fridge and found two temperature sensor located in the top part behind the cover (one on the left side of the fan and the other one on the right side of the cooling system)
I found my model and the version and changed the sensors (see short story)
I think this sensor had a problem

But I changed the other sensor too (connected to the top)

Finally after so much time and money I fixed this issue!
Hope this can help some people who have a similar issue with this fridge.
Good luck
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Thank you for the post. I had the same issue with the same fridge.

First replaced the DA32-10104N temperature sensor (this video https://www.youtube.com/watch?v=I_aDS77dY8o).

The fridge was still freezing food so I replaced the second sensor and it started working again. This video shows how to replace the DA32-00011C sensor (slightly different fridge, but same method/location). https://www.youtube.com/watch?v=6Cm0ReZsMPw

I am having a problem with my Samsung fridge freezer model rf24fsedbsr which is freezing the food in fridge section , this problem came about 2 years ago first with the ice dispenser getting blocked with all the ice clogged up, defrosted it and then soon after there was some noise from the back panel like the fan not being able to turn freely and soon after the fridge was getting colder and started freezing up all the fresh food and eversince I have been having to turn off the fridge nearly every night, sometimes I would forget to turn off and the fridge would start to freez the stuff. Any suggestions to correct the problem please? Thanks Firooz

I am having a problem with my Samsung fridge freezer model rf24fsedbsr which is freezing the food in fridge section , this problem came about 2 years ago first with the ice dispenser getting blocked with all the ice clogged up, defrosted it and then soon after there was some noise from the back panel like the fan not being able to turn freely and soon after the fridge was getting colder and started freezing up all the fresh food and eversince I have been having to turn off the fridge nearly every night, sometimes I would forget to turn off and the fridge would start to freez the stuff. Any suggestions to correct the problem please? Thanks Firooz

Me too it seems to be a problem with these models. My question is how long did it fix it for you Mike? I have had best buy tech out five times in two years he replaced all my temp sensors two years ago now same problem!