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How do I replace a Defrost Timer in an Upright Freezer?

The board houses the light bulbs. The light board has an electronic circuit board that controls the light bulb's voltage. When the electronic circuit board is malfunctioning, you can see a burn mark. If the light board doesn't light up, replace it.

The door seal is attached to the door panel of the upright freezer and the lid is attached to the chest freezer. The seal keeps air out of the freezer when the door is shut. When the door or lid is closed, a damaged seal lets warm, moist air into the freezer. The door seal should be replaced if it is damaged.

The freezer defrost sensor is located next to the evaporator. It goes when the temperature in the evaporator is too high. The defrost bi-metal shuts off when it travels. A malfunctioning defrost bi-metal causes frost to build up on the evaporator and causes a warmer freezer interior. The defrost sensor should be replaced if it prevents the heater from working.

The freezer has a temperature sensor. The control board uses the thermistor to read the temperature in the freezer. If the thermistor isn't accurate, replace it.

The length of the cycle can be limited by the defrost timer. During the defrost session, the timer stops the compressor from running and causes the frost to melt from the evaporator fins. The defrost timer needs to be replaced if it doesn't work correctly.

Follow these steps to fix your issue:

  1. Disconnect the electrical power

    Shut off the circuit breaker for the freezer if you want to unplug it.

  2. Remove the light lens

    To remove the light lens from the freezer wall, use a small screwdriver.

  3. Remove the LED light board

    Release the light board from the housing by Prying out the light housing locking tabs. Remove the locking tabs from the wire harness plug and the wires from the light board. The light board is in the freezer.

  4. Install the new LED light board

    The wire harness should be plugged into the light board. The housing has a new light board.

  5. Reinstall the light lens

    Attach the light lens to the housing by positioning it over it.

  6. Restore electrical power

    You can restore power by plugging in the freezer or the house circuit breaker.

  7. Disconnect the electrical power

    Shut off the circuit breaker for the freezer and unplug it. If you want to keep the food fresh, move it to a cooler. Most frozen foods will not be affected by the 45 minutes without power in the freezer.

  8. Remove the evaporator cover

    The drawers are in the freezer. The screws are on the cover. Remove the cover from the freezer.

  9. Remove the thermistor

    The thermistor mounting screw can be removed. The old thermistor needs to be removed before the wires can be cut.

  10. Connect the wires to the new thermistor

    The end of the wires in the freezer have insulation on them. The wires need to be cut about 4 inches from the thermistor. Use wire nuts to connect the wires.

  11. Install the new thermistor

    Attach the new thermistor to the wall with a screw.

  12. Reinstall the evaporator cover

    Go to the back wall and position the cover. There are drawers inside the freezer cabinet.

  13. Restore electrical power

    You can restore power by plugging in the freezer or the house circuit breaker.

Time required:

45 minutes.

You would need the following tools:

phillips screwdriver, wire stripper, work gloves.

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