William H Troy , MO November 14, 2020 Appliance: Whirlpool Refrigerator GS6NVEXSL01 Whirlpool Refrigerator Gs6nvexsl01: Side by side refrigerator freezer would not get down to freezing point. It seemed as if items in the freezer were mushy as if the defrost cycle was always on and no vents were blocked.. How to replace Refrigerator Defrost Thermostat. I replaced the defrost thermostat and the compressor capacitor. I really do not like working on side by sides as they are difficult cramped access to work on. But I was successful. It's likely I did not need to replace the capacitor though as I believe the fix was the defrost thermostat. 5 People found this story helpful Do-It-Yourself Rating: Repair Time Estimate: 30-60 minutes