An AC evaporator core is an important part of the air conditioning (AC) system in your vehicle. It is typically located underneath or inside of the dashboard.
The evaporator core (or simply “evaporator”) receives liquid refrigerant as it passes through the expansion valve or fixed orifice tube. There inside the evaporator, the low-pressure liquid reaches its boiling point and turns to a gas. When this happens, it absorbs heat from the surrounding air - a lot of heat - causing the evaporator coils to cool considerably. Air passing through the cooled coils is blown into the passenger compartment through the vents.
The procedure to replace an AC evaporator core depends on the vehicle make and model as well as its location. Vehicles with rear AC often have two evaporator core units, one inside the dashboard and the other behind an interior trim panel in the rear cargo compartment. Gaining access to either location can be a challenge.
The evaporator is mounted inside the HVAC housing. In general, a technician will take the following steps to remove the housing and replace the evaporator core: