I have a Frigidaire Model #ffhs2611pf5, about 7 yrs old, purchased new when I bought my house.

Last year I noticed the water line froze up coming to the freezer side door, after some troubleshooting I found that the line was frozen inside the door because the freezer was too cold, more frost than usual in the freezer side. If I left the door open for a while and covered the freezer items with a blanket, the line would thaw and the water worked for a bit. Until I closed the door and it froze back up. So I started my journey of trying to find out why. Here are the steps I have taken.

1. Replaced Defrost Thermostat Kit (Part # 5303918214). Did not fix issue.

2. Checked continuity on the Defrost Heater. Continuity confirmed, so I did not replace this part. But while the freezer was open I verified there was not excessive frost build up on the coils (ie. it was not frozen over). I also verified that the top cold air exit was not blocked by ice and that the bottom cold air intake was not blocked by ice (a common issue according to YT).

4. AppliancePartsPros expert chat sad it was likely the Evaporator Fan Motor (Part # 808602602). I ordered this part and pulled the freezer panel back off but verified the evaporator fan was running fine. So I returned the motor without installing.

3. As a test, and DIY Youtuber recommended I put some insulating tape on the inside of the freezer door panel... which actually worked for a while. Prevented the overly cold air from freezing the water line and my water worked for a week or so. Then that tape got so cold it all froze again. LOL.

4. I also note that adjusting the temp setting on the control board does nothing. The temp does not change on the freezer side or the fridge side up or down, it just seems to stay on maximum cold no matter if on 1 or 9. Weirdly the On/Off button does work. So I ordered a new "Electronic Control w/ cover" (Part # A01078804). This did not fix the issue either. Still overly cold freezer and no temp adjustment available.

5. I was concerned the Damper Assembly might be to blame, but I have successfully verified that the door is opening and closing on it's own, allowing the cold air to travel from the freezer to the fridge side. So I have not replaced this part.

I guess this all leads me to the Thermistor Assembly (Part # AP5802148). My understanding of this part is that the thermistor takes the current temp of both sides and sends it back to the control board, which then regulates the temp accordingly (IE. turning the defrost on/off, triggering the damper, etc). I understand there is a way to test this part with a multimeter but the one I have doesnt have leads small enough to fit in the pins.

I assume that if the thermistor is not working, the control board wont get an accurate reading of the temp and just continue to blow cold air all the time. Does that sound right?

As you can imagine, I am not enjoying swapping parts to no resolve. But the fridge works pretty well aside from freezing up my water line, so I am hesitant to replace the entire thing if it's a simple part swap to fix. Thanks in advance.