When the system is running under refrigeration, ice forms in the evaporator coils. This occurs due to condensation and subsequent solidification of the moisture (H2O) contained in the air in the chamber's internal environment when it touches the “cold” surface of the coils.
As the chamber doors open and close, there is also a renewal of the internal air and thus the supply of moisture, which will freeze between the evaporator fins and may cause its blockage due to excessive ice formation. This ice deposited between the fins acts as an insulator between the ambient air and the refrigerant, so that the refrigerant does not receive the amount of heat appropriate to its complete vaporization, thus causing the risk of liquid blow in the system compressor. .
It is then necessary to perform an operation called defrosting in the system, this defrost consists in completely melting all the ice formed between the evaporator fins. There are basically three ways to perform defrost on the commercial line: natural defrost (which can occur through forced air circulation between the evaporator fins), electric resistance defrost and hot gas defrost (using overheated steam).
