When using a refrigerated truck, care should also be taken to keep the inside of the REFRIGERATED BOX clean. Due to the evaporator fan, air is circulated through the compartment, causing ground debris or dust to be drawn in by the evaporator fan. Long-term, this will cause a large number of impurities to be drawn into the evaporator coil, the coil is surrounded by impurities, and the heat exchange rate will drop. Therefore, after several years of use of refrigerated vehicles, users usually feel that the cooling effect is not as good as before, other than the vehicle itself fault, it is because the coil is too dirty. Therefore, to ensure that the box ground clean is the key to ensure that the normal work of the refrigeration unit.