Methods and systems for defrosting a transport climate control system evaporator

A method for defrosting an evaporator of a transport climate control circuit of a transport climate control system that provides climate control to a climate controlled space of a transport unit, the transport climate control circuit including a compressor, an evaporator that includes an evaporator coil having an inlet side for receiving a working fluid from an inlet of the evaporator coil, the inlet side extending from a first side of the evaporator coil to a second side of the evaporator coil, and an outlet side for returning the working fluid to an outlet of the evaporator coil, the outlet side extending from the first side of the evaporator coil to the second side of the evaporator coil, at least two fans, an electric heating device, and a damper that moves between at least an open position and a closed position to separate the evaporator from the climate controlled space and to control an amount of the air flow between the evaporator and the climate controlled space, the method comprising:

• a controller of the transport climate control system detecting a defrost event condition;
• upon detecting the defrost event condition:
• closing the damper when a defrost event is triggered to separate the evaporator from the climate controlled space,
• supplying heat to or around the outlet side of the evaporator coil by turning on the electric heating device to generate heat, wherein the electric heating device is positioned on the outlet side of the evaporator coil and only extends across the evaporator coil between a first side and a second side on the outlet side of the evaporator coil;
• independently controlling a first fan of the at least two fans to move air around the evaporator coil in a first controlled direction so that heat from the electric heating device at the outlet side of the evaporator coil at one of the first side or the second side of the evaporator coil is used to convectively heat frost formed on the inlet side of the evaporator coil, and
• independently controlling a second fan of the at least two fans to move air around the evaporator coil in a second controlled direction so that heat from the other side of the evaporator coil is only used to convectively heat the inlet side of the evaporator coil.