Mitsubishi Electric: Smart Defrost

Heat pumps are an efficient and sustainable systems for the production of thermal energy. Air-cooled models transfer thermal energy between outdoor and indoor air to heat rooms. During this process the outside air passes through the finned coils of the evaporator and it is cooled; if the air temperature reaches the dew point, part of the water vapor contained in it can condense, freezing in contact with the cold surface of the fins. The formation of ice on the coils leads to a reduction in the heat exchange of the pipes and an increase in pressure drops. This phenomenon can become a vicious cycle leading to the formation of more ice. So, in order to continue to provide the required heat load and restore optimal working conditions it is necessary to remove this icy layer from the evaporator of the unit.