RF26HFENDSR/AA 0002 Fridge compartment cools to ~42, Freezer Fine, tried a lot of things.... stuck.

[Balbanes]

Hi! New to the forums. Worked through the "warm refrigerator" flowchart, but my refrigerator appears to be a "twin cooling" model where the freezer and fridge compartments dont share air (or at least I dont see where any air could be moving around from one side to the other).

My model is a Samsung RF26HFENDSR/AA 0002 French Door model. The ice maker is in the freezer, so the refrigerator compartment does not have an ice chest.

Anyway, symptoms:

• About 1-2 years ago the fridge was full of water. I pulled apart the back panel and saw that the evaporator coils were frozen up. Defrosted it, put it back together, and it did it again in about 9 months. Defrosted again and it froze up 3 months later. That's when I realized something needed to be done.
• Fridge digital dial reads 37 degrees
• Manual temperature gauge (https://www.amazon.com/gp/product/B089NLQ7SF/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1) reads ~42-44. I have two of these, one at the top and one at the bottom of the compartment, submersed in a pint glass filled with water
• Refrigerator is about 1/2 full of non-perishables (alcohol, canned food, etc.) just to help it maintain a consistent temp/reading

 

What I've done so far:

1. Replaced the temperature sensor with a new OEM part, thawed and dried the evaporator coils. Did not resolve
   • On this step I also replaced the small metal tab that hangs over the drain hole with a much larger/thicker piece that hangs down much further. I trimmed it to make sure it would not actually rest against the walls of the drain hole (was worried it would get too hot and damage anything it sits against over the long-term).
2. Tried to set the offset based on some forum posts. Basically it told me to set my fridge offset to 15 to trick the temp probe. Did not resolve
3. Replaced the evaporator fan. Did not resolve
   • Tested the original fan using a 12V adapter stripped at the ends and it spins up without issue
4. Opened the control board cavity and immediately smelled burnt electronics. Pulled out the control board and there seems to be a dark brown spot under it about the size of a dime. The integrated circuit that sits over that spot smells pretty rough. Ordered new control board
5. Thawed and dried the evaporator coils. Installed the new control board, reinstalled the original fan. It is now about 14 hours later and the digital gauge reads 37, but the manual gauges read 42-44. I checked the water that the manual gauges are submerged in using a different digital cooking thermometer--it reads 44. Did not resolve (?)
6. After plugging the fridge back in, i used magnets to trick it into thinking the doors were closed so I could listen for the fan to spin up. It spins up just fine.

 

Notes:

• I should have tested both the original temp probe and new temp probe using a multimeter... my guess is the original probe was just fine but its long-gone now. I technically haven't tested the new probe but I doubt it is bad. Still, I should have done this (didn't think to do it until I read another post on a different thread recommending it) to be sure
• I should have tested to see if the fan spun up on the original motherboard using the magnet trick I mentioned in #5 above, didnt think to do this until after the new control board was already in
• Refrigerator is about 5 years old.

 

The flowchart says to disassemble the freezer to get eyes on the evaporator coils, but my fridge has a set of evaporator coils in the fridge compartment... and the freezer is working fine. I assumed that since mine is a twin cooling system, "eyes on the evaporator coils" in the fridge compartment was correct (right?).

According to the flowchart, fuzzy frost on the coils says to troubleshoot the defrost system, but I couldn't find a good resource after clicking the "CLICK" button.

What else should I do? I feel like its not a refrigerant leak because it has no problems cooling the freezer and it freezes up the fridge coils without issue. I thought maybe replacing the heating element under the evaporator coils might be next? Just not sure here and I'm kinda getting tired of being without a fridge for what is now about 3 weeks.

 

Any help you can provide would be greatly appreciated!! Thanks in advance. :)

 

 

[Balbanes]

Update:

 

Pulled it apart again, it was already freezing up. The heater and defrost thermostat are integrated in this model. Submerged the thermostat into ice water and tested for continuity. Nada.

 

Ordered a new heater/thermostat unit and it will be here tomorrow. Fingers crossed!

[Slav]

On 8/7/2021 at 1:29 PM, Balbanes said:

Submerged the thermostat into ice water and tested for continuity. Nada.

Not all thermostats can be tested this way because the closing temperature could be much colder than the ice-water.

For example; if it says on the thermostat let's say L55-35F, that means the continuity closing temperature is 55-35 = 20°F

The better way to test it is to put the thermostat in a working freezer for a while.

[Slav]

On 8/6/2021 at 9:26 AM, Balbanes said:

the fridge was full of water. I pulled apart the back panel and saw that the evaporator coils were frozen up. Defrosted it, put it back together

When you defrosted it, did the water easily go down the defrost drain pipe? You can pour some water under the evaporator and observe. If it's hardly draining, you need to clean the drain tube and possibly replace the "duck bill" on the drain tube outside, next to the condenser coils.

Also, if the evaporator cover Styrofoam was soaked in water, you need to dry it very well or maybe even replace the cover.

[Balbanes]

On 8/8/2021 at 6:18 PM, Slav said:

Not all thermostats can be tested this way because the closing temperature could be much colder than the ice-water.

For example; if it says on the thermostat let's say L55-35F, that means the continuity closing temperature is 55-35 = 20°F

The better way to test it is to put the thermostat in a working freezer for a while.

 

Thanks for the response! This is a 60/40 thermostat.

 

On 8/8/2021 at 6:30 PM, Slav said:

When you defrosted it, did the water easily go down the defrost drain pipe? You can pour some water under the evaporator and observe. If it's hardly draining, you need to clean the drain tube and possibly replace the "duck bill" on the drain tube outside, next to the condenser coils.

Also, if the evaporator cover Styrofoam was soaked in water, you need to dry it very well or maybe even replace the cover.

 

Yeah, the very first time I had to go through this process, the drain hole was plugged with ice. So I put in a longer/more substantial drain tube "heater"(?), basically a small tab that hangs off the bottom of the heating element and into the drain tube. It does not plug up now at all.

 

Update:
I was FINALLY able to get the fridge back down to temp. After replacing the heater, it got down to temp for about 3 days, so the thermostat was definitely a problem. 

Now its freezing up again. I've tried running the manual defrost cycle for 20 minutes a couple times and it doesnt seem like it is enough. The internet said to run it about 20 minutes, so that's why I chose that timing. I just let it run about 40 minutes and it looks like its designed to run for about that long. While in manual defrost, it beeps every second or so. If you just let it go completely, it will eventually stop beeping. IMO that's signifying that the cycle is complete. Unplug it for about 15 seconds after and then plug it back in and you're good.

Anyway, there's a fix on youtube that I'm going to try, parts come in today. Ultimatley, I suspect that the refrigerant has gotten low... it seems like when that happens, the refrigerant line likes to freeze up close to where it enters the refrigerator. I really don't want to tap into it and recharge it because it'll just leak out again and the stuff is awful for the environment. Going to try this secondary heater trick and see how it goes. I'll report back with my results.

 

[Balbanes]

Oh btw, forced defrost instructions for my model, for the next person trying to trouble shoot:

Hold "Power Freeze" and "Fridge" until you get a blank screen

Press any button until you see the following:

Fd = full defrost (top + bottom)

rd = fresh food defrost

It will start to beep, beeping signifies that its working. Let it go until it stops beeping. Unplug for ~15 seconds and plug it back in.

[Slav]

Good luck!

Let us know how the extension heater works for you.