Which two types of defrost are commonly used with low temperature refrigeration fixtures?

Hot gas and electric defrost are commonly used methods for managing frost accumulation in low-temperature refrigeration fixtures.

Hot gas defrost takes advantage of the refrigeration system's own heated refrigerant to melt the ice or frost. During this process, the flow of refrigerant is diverted from the evaporator to the receiver or compressor, where it is sent back to the evaporator in a heated state. This method is efficient because it utilizes existing system components and minimizes downtime in the refrigeration cycle, allowing for effective frost removal without requiring additional energy for separate heating elements.

Electric defrost, on the other hand, employs electric heating elements that are installed in the evaporator or around the refrigeration unit. When activated, these elements provide the necessary heat to defrost the coil by directly increasing the temperature of the frost or ice. This method is straightforward and can effectively clear frost, but it may take longer than hot gas defrost and can lead to increased energy consumption due to the additional electrical heating.

These two methods are widely adopted in low-temperature settings where frost build-up can significantly affect efficiency and performance, as they both offer reliable solutions for maintaining optimal operational conditions. Other options, while they may represent various defrost techniques, do not specifically align with common practices in low-temperature