Sub-Zero Refrigerator Error Code 20 2 07

Error code 20 2 07 indicates a defrost bi-metal error. The bi-metal thermostat is a thermal safety device wired in series with the defrost heater on the evaporator assembly. When the control board detects the defrost circuit is not functioning correctly through this component, it logs this fault. The issue typically points to a failed bi-metal thermostat or a burned out defrost heater.

A reset may temporarily clear the fault code from the display, but if the underlying component has failed, the error will return once the control board attempts the next defrost cycle. The bi-metal thermostat or defrost heater must be tested and replaced as needed to permanently resolve the code.

Repair costs vary depending on which component has failed and local labor rates. A defrost heater or bi-metal thermostat part typically costs in the range of $30 to $150 depending on the specific model. With professional labor, total repair costs commonly fall in the range of $150 to $400. Sub-Zero appliances often require technicians familiar with the brand, which can affect the labor rate.

A knowledgeable DIYer can begin diagnosis by using a multimeter to check continuity across the bi-metal thermostat and resistance across the defrost heater element. If either component tests open, it will need to be replaced. However, accessing the evaporator compartment on a Sub-Zero refrigerator requires removing interior panels, so comfort with appliance disassembly is necessary before attempting this repair.

The refrigerator may continue to cool in the short term, but without a functioning defrost cycle, frost will accumulate on the evaporator coil and progressively restrict airflow. This will cause the unit to lose cooling efficiency and could eventually lead to food spoilage. It is advisable to address this fault promptly rather than continuing to run the unit unrepaired.