A refrigerated merchandiser including a case defining a product display area supporting product and an evaporator disposed in an air passageway in fluid communication with the product display area via an outlet to direct a refrigerated airflow into the product display area. The merchandiser also includes a control system in communication with and programmed to control the refrigeration system so that the product display area is maintained within a predetermined temperature range. The control system also varies the temperature of the refrigerated airflow through the outlet above an airflow temperature threshold between about 35 degrees Fahrenheit and 41 degrees Fahrenheit at least once during a predetermined time period to avoid formation of frost on the evaporator while maintaining the product display area within the predetermined temperature range.