Magic Chef Refrigerator CTB1925DRB Freezer not defrosting

This defrost timer controls the automatic defrost cycle in select refrigerators and freezers, switching between cooling and defrost to clear frost on the evaporator. It helps maintain stable temperatures and prevents heavy ice buildup and long run times. What it does:

• Alternates the system between cooling and defrost on a timed schedule
• Sends power to the defrost heater during defrost, then returns power to the compressor and fans
• Failure can cause heavy frost on the evaporator/back freezer wall
• May lead to warmer temperatures, constant running, short cycling, or no-cool if stuck in defrost

• 1 defrost timer

• Disconnect power before servicing
• Access location varies by model
• Note wire positions and transfer them one at a time to the new timer
• Mount securely in the same orientation as the original and verify normal cycling after power is restored

This defrost thermostat is the temperature limit switch for the evaporator. It lets the defrost heater run when coils are icy and opens as they warm to end the cycle, helping stop frost buildup and restore steady cooling.

• Monitors evaporator temperature; closed when cold to allow the defrost heater to energize
• Opens as the coil warms to terminate defrost and protect components from overheating
• Failure may cause heavy frost on the back wall/evaporator and weak airflow or a warm refrigerator section
• Can also lead to long run times or cooling that returns only briefly after a manual defrost

• Unplug the refrigerator or disconnect power before servicing
• Located behind the freezer's rear panel on the evaporator; remove shelves/ice bin and panel to access
• Reinstall in the same position/clip for firm contact with the coil or tubing
• Make secure, insulated wire connections and route wiring away from sharp edges and moving parts