Sub-Zero 650 model shows error code 21 (Defroster Overheat) EC
Sub-Zero 650 shows error code 21 (Defroster Overheat)EC 21 has been showing for about 6 months. If I open the circuit breaker the EC clears, but returns later. I have cleaned the heat exchangers. The refrigerator runs just fine. What’s the problem and what can I do to fix it?
Expert: Dennis replied:
Sub-Zero Error code: EC21EC24 Cause of error code: Defrost Functionality Issue Solution 1: If temperatures are high call for service. Solution 2: If temperatures are near normal range: a – Clean the condenser b – Press and hold the door ajar alarm key for 15 seconds to clear the error code c – If EC Service light appears, or temperatures rise contact service for repair: 800-440-8583
Defrost overheats means the defrost temperature exceeded the temperature where the heater should have stopped already. This is a problem with the defrost termination thermostat. This part should have open up the heater circuit already once the temperature of the evaporator is above freezing temperature.
Why do I have to clean the refrigerator condenser?To help assure efficiency and proper operation, the condenser on your refrigerator must be cleaned regularly. The condenser relies on airflow to work properly and any obstruction can cause the unit to fail. A Sub-Zero refrigerator will use less energy than a 100-watt light bulb when running at peak performance; however, failing to clean the condenser may cause the unit to run excessively. If the condenser is not cleaned properly, mechanical components in the unit may fail prematurely. If you have pets, you may have to clean the condenser more often than the suggested three to six months.
How often should I clean my Sub-Zero refrigerator condenser?Cleaning the condenser is important for the overall operation of your Sub-Zero refrigeration unit, and we recommend vacuuming the condenser six to 12 months. A dirty condenser will affect the cooling functions, leading to warm temperatures in the refrigerator and freezer and may even cause condensation or frost buildup inside the compartments.
How should I vacuum the condenser of my Sub-Zero?Before cleaning any Sub-Zero model, shut the electricity off at the control panel. Use a soft-bristle brush and vacuum to remove dust and lint from the condenser. Be sure to wear gloves to avoid injury from the sharp condenser fins.
To avoid bending the condenser fins, vacuum up and down in the direction of the fins. We can help you over the phone, or you can schedule the annual condenser cleaning at a discounted rate. To schedule your annual service, click here or call us: 800-440-8583
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