1. Shut off power to the WPU.
2. Remove the bottom front, bottom left, and bottom right panels.
3. Remove the wire junctions to the evaporator fan.
   
4. Remove the 6 screws securing the fan assembly to the unit.
   
5. Remove the fan assembly from the unit.
6. Use a torch to unsolder the evaporator inlet and outlet joints.
   
7. Remove 2 screws (one on each side) securing the coil to the sides of the unit.
   
8. Remove the frontal screws under the air filter.
   
9. Remove the screws behind the fan assembly.
   
10. Remove the thermal insulation behind the compressor compartment and remove the screws under it.
    
11. Remove the bolts and screws securing the coil to the frame.
    
12. Pull the top part of the frame upwards until the evaporator coil can be removed.
13. Replace the coil and reattach all mounting screws.
14. Use a torch to solder the condenser inlet and outlet.
15. Replace the evaporator fan assembly and reconnect the wiring.