Just so we are on the same page I will explain what a Refrigerators defrost timer does and where the defrost timer is located on a top mount refrigerator freezer.
The Defrost timer tells the refrigerator when to go into defrost. The mechanical timer is set to run for 8 hours and then go into a defrost cycle for 30 min, during which time voltage is applied to the refrigerators defrost heater.
If you have ever heard a hiss from the freezer side of your refrigerator it is a good chance the refrigerator was in defrost melting the frost on the evaporator and dripping onto the heater located below the evaporator in the freezer section.
Where is the Refrigerators defrost timer you ask, on top mount refrigerators it is located in the cold control housing, this is the part that houses the refrigerators controls, pictured below.
Tucked up inside this housing is the defrost timer, it will be mounted down with several screws. If your refrigerator is stuck in defrost and the compressor is not running the defrost timer may need to be replaced.
To determine if the timer is stuck in defrost take a flat head screw driver and place it in the timers plastic slots, rotate the screwdriver to advance the timer in and out of cool mode. There is a small cut out in the cold control housing to insert the screwdriver, here is a picture of a refrigerators defrost timer being manually advanced.
The timer will click when rotated, when you hear the timer click out of the long rotation it is in defrost. I hope this article has helped you in you appliance repair journey, If you have a moment drop us a line and let us know it did, I sure appreciate getting those emails.