How to Troubleshoot & Replace Whirlpool AP6010356 / WP67003426 Defrost Thermostat

I had had the same problem 4 or 5 years ago and spent close to $200 to repair it. I did have the slip from that repair with part #'s so I went ahead and ordered a defrost timer and thermostat. You-tube had plenty of videos on replacing those parts and even before they arrived I was able to add a switch and bypass the broken thermostat and start a cycle manually with the timer. (which it seems was was still functional). Between that and cycling some ice packs up from the still working freezer I lost very little food. The service from here was quick and accurate, I got real OEM parts in a short time. Thank you. 

First, I turned the breaker off, removed all the food and put a fan in front of the open freezer door (French Door model) and defrosted for a few hours then turned the unit back on and reloaded the food. It worked for a week then happened again. I ordered a new defrost thermostat but before putting the food back in, I removed the old thermostat and tested it in the ice water routine. It failed the test so, I thought I was on the right track. The unit worked well enough till the new part arrived. I tested the NEW part and the OLD part and BOTH failed the ice water test!!!! With nothing to lose, I put the new one in anyhow and it has worked PERFECTLY for several days. Out of curiosity, I put the old thermostat in the freezer (at zero degrees) overnight and tested it. It worked perfectly after an overnight cold soak. Not sure I accept that the cold water test as an accurate measure of the function of thermostat. BUT the new thermostat DID make the difference and I am going with that!!! I did notice that with the OLD thermostat, the freezer control would not adjust properly --- got cold but seemed to have it's own mind. It wanted to go much colder than I wanted so, I let it stay down there. With the NEW thermostat in place, I can adjust it to my preferred setting which is zero. Replacing the thermostat was just a few minutes but moving the food and defrosting can take w couple of hours. Good luck!!! 

The refrigerator was warm but the freezer was cold. Turn off the refrigerator for 24 hours. Plugged the refrigerator back in, the compressor was not kicking on but the condenser fan and evaporator fan were running. Pulled start relay, measured between two bottom points found Open.. replaced start relay and capacitor and compressor stared immediately and everything worked normally. 

Replaced evaporator fan and allowed evaporator coil to defrost. After two days, evaporator coil was frosted over again. Ordered defrost thermostat and heater. Replaced thermostat, check continuity of defroster heater element. Had continuity so did not replace at this time. So far everything working and refrigerator compressor fan does not run constantly thus appears to be going into defrost mode. Keeping defrost heater for a couple more days to be sure evaporator coil does not ice over again. Instructional repair videos related to trouble shooting and parts replacement were extremely helpful and appreciated. Without them, repair would have been much more difficult. Love this site now for all my appliance parts and repair needs. 

Although I replaced the heater coil the root cause was the sensor on evaporator return copper tube. I ordered both parts and choose to test the heater coil first. To rest heater coil I had to remove coil in order to access connectors at each end to measure resistance. Due to the level of difficulty in removing coil,I choose to replace coil while I had it out. The sensor is a much easier repair. The online Videos would have been nice before I purchased parts. One of the videos (heater coil replacement) didn't represent the model I had but was general enough for me to understand the procedure. 

FREEZER ON BOTTOM. TOOK OUT DRAWERS AND BACK PANEL. USED A HAIR DRYER TO DEFROST COILS THEN PUT IN A NEW HEATER, DEFROST & DEFROST THERMOSTAT. I FIGURED THEY WORK TOGETHER AND HAD THE SAME WEAR PLUS WAS EASIER TO DO AT ONE TIME. 

Replaced thermostat (cut the 2 wires, spliced new thermostat). Did need to remove drawer (tricky slide out) icemaker (3 screws)and back panel (4 screws). Had to adjust the fridge and freezer cold levels over the next 24 hours to get temperature just right. 

I replaced the defrost thermostat and heating coil. The refrigerator/freezer is operating. Time will tell to see if it freezes up. AppliancePartsPros.com videos and parts won the day. Thanks 

This problem started 5 or 6 years ago. Warm refrigerator section. The first time we just emptied the fridge and freezer and left the door open for a few days, then plugged it back it to see if it would still work or if it was time to buy a new one ( the unit was only about 2-3 years old ). Well, it started working. This is about the 4th time it happened and I was ready to just buy a new one. I knew it was freezing/icing up but didn't know why. I started wondering about the defrost cycle. This time the online search for problems with my model number brought me to AppliancePartsPros.com. My problem was top of the list in the customer story section. Now I had confirmation of the problem and a way to fix it. The repair video made the part replacement so easy. Replacing the electronic control board really did only take about 5 minutes and it only took a flathead screwdriver. Just too easy. And the fridge is just purring now. With the parts easy to find and the self-help videos available it is time to throw away the link to the repair shop and replace it with AppliancePartsPros.com 

Unfortunately, replacing the defrost thermostat did not fix it and the suspected control board is no longer available. But the Appliance Parts Pros web site is fantastic, especially the videos, as is their service. The part arrived 26 hours after I ordered it without paying for premium shipping.