How is defrost normally accomplished in a medium temperature case?

Defrost in a medium temperature case is accomplished by leaving the case fans operating and shutting off the compressor. This method effectively allows the accumulated frost or ice to melt without completely stopping airflow within the refrigeration system. When the compressor is turned off, the temperature inside the case will rise slightly due to the lack of cooling, which is necessary to facilitate the melting of frost.

By keeping the case fans running during this process, airflow helps to distribute the warmer air throughout the unit, encouraging the melting frost to evaporate and preventing moisture buildup. This approach helps maintain a more even temperature and efficient defrosting process while ensuring that the food inside the case remains at a reasonable temperature until the defrost cycle is completed.

The other methods listed would not be as effective or practical. For example, completely shutting off the refrigerator can lead to longer defrost times and potential issues with food safety. Removing the case from service is not typically necessary during defrosting, as it can create downtime and impact operations. Running the compressor continuously would not allow for effective defrosting since it would keep the temperature low, preventing frost from melting.