The part(s) or condition(s) listed below for the symptom Freezer runs all the time are ordered from most likely to least likely to occur. Check or test each item, starting with the items at the top of the page.
The evaporator fan motor draws air over the evaporator coils and circulates it throughout the freezer. On most refrigerators, the fan motor will not run when the door is open. Make sure that the refrigerator door is closed and the door switch is activated. If the door switch is activated but the evaporator fan motor still won’t run, replace the evaporator fan motor.
Refrigerator evaporator fan motor assembly with wire harness, 115 volts. *Per manufacturer screw holes in motor are not threaded from the factory, use old screws. See Related Items for self tapping screw. When the evaporator fan motor fails, it often generates a lot of noise in the freezer area.
The defrost heater turns on several times throughout the day to melt away any frost that may have accumulated on the freezer evaporator coils. If the defrost heater assembly has burned out, the evaporator coils will frost over. If the evaporator coils are frosted over, air won’t be able to pass through the coils and cool the freezer. To compensate for the decrease in cooling capacity, the freezer will run continuously in an attempt to keep the freezer cold. If you suspect that the defrost heater isn’t working, first check the evaporator coils. If the coils are plugged with frost, the defrost system is not working properly. Next, use a multimeter to test the defrost heater for continuity. If the defrost heater does not have continuity, replace it.
The defrost heater turns on several times throughout the day to melt away any frost that may have accumulated on the freezer evaporator coils. Before the defrost heater turns on, the defrost thermostat must sense that the evaporator coils are cold enough. If the coils are cold enough, the defrost thermostat will allow the defrost heater to turn on. (Usually, the temperature of the coils must be below 30 degrees Fahrenheit.) If the thermostat is defective, the defrost heater won’t turn on, causing the evaporator coils to frost over. To determine if the defrost thermostat is at fault, use a multimeter to test the thermostat for continuity. If the defrost thermostat does not have continuity, replace it.
If the condenser coils are located within the freezer walls, the coils do not require cleaning. However, if the condenser coils can be readily accessed from behind or under the unit, you should clean them every 6-12 months. If the condenser coils are dirty, they won’t be able to dissipate heat effectively, greatly reducing the cooling capacity of the freezer. If the condenser coils are dirty or have not been cleaned in a while, clean them.
If the freezer only freezes the top shelf, there may be a sealed system leak in one of the shelves. Sealed system repairs are usually cost-prohibitive. If the sealed system is leaking, you will probably need to replace the freezer.