A/C Evaporator Cleaning

A/C EVAPORATOR CLEANING

Some vehicle operators may experience a musty odor from the A/C system, primarily at start up in hot and humid climates. This odor may be the result of microbial growth on the cooling coil. During normal A/C system operation, condensation forms in and around the A/C cooling coil. When airborne pollutants mix with this condensation, bacteria and fungi growth begins and odor may result.

If the vehicle operator experiences a musty odor when operating the A/C system, perform the following procedure.

WARNING: Always use eye protection, rubber gloves and protective clothing when performing the following procedure. Avoid continuous breathing of vapors from evaporator coil cleaning and sealing fluids. Avoid contact with skin and eyes. Failure to follow these instruction may result in possible serious or fatal injury.

1. Remove the cowl panel cover (refer to 23 - Body/Exterior for more information).
2. Clean any dirt and debris that may be present at the HVAC fresh air inlet screen and at the top of the cowl panel.
3. Install the cowl panel cover.
4. Raise and support the vehicle.
5. Inspect the evaporator drain hose or tube (depending on application) for foreign material that may be blocking the drain and repair as necessary.
6. Once drain operation has been verified;
- when equipped with a rubber drain hose, temporarily pinch the drain hose closed using an appropriate pair of heater hose pliers.
- when equipped with a solid plastic drain tube, obtain an appropriate size rubber or plastic cap or plug and temporarily cap or plug the drain tube.

7. Lower the vehicle.
8. Place a protective cover over the front passenger side floor and seat area.
9. Remove the blower motor Blower Motor - Removal.
10. Remove the blower motor resistor or power module, depending on application Blower Motor Resistor - Removal or Blower Motor Power Module - Removal.
11. Clean any dirt and debris that may be present inside the HVAC blower motor housing and all readily accessible areas inside the HVAC housing. If necessary, use a vacuum with a small flexible hose, and take caution not to damage the evaporator core fins.
12. Using PSE Flex Spray Delivery Tool 534-62637 or equivalent, completely coat the entire surface of A/C evaporator with three bottles of Mopar(R) Cooling Coil Cleaner through the blower motor and power module or resistor openings. Be sure to use all of the coil cleaner in each container.
13. Allow the vehicle to sit for 30 minutes.
14. Raise and support the vehicle.

WARNING: Excess cooling coil cleaner will drain from the evaporator housing when the clamp, cap or plug is removed from the evaporator drain hose or tube. Always use eye protection, rubber gloves and protective clothing. Avoid continuous breathing of vapors from evaporator coil cleaning fluid. Avoid contact with skin and eyes. Failure to follow these instruction may result in possible serious or fatal injury.

15. Remove the previously installed clamp, cap or plug from the evaporator drain hose or tube and allow excess coil cleaner to drain from the HVAC housing.
16. Lower the vehicle.
17. Refill the three empty coil cleaner bottles with clean tap water.
18. Using PSE Flex Spray Delivery Tool 534-62637 or equivalent, completely rinse the entire surface of A/C evaporator with the three bottles of clean tap water through the blower motor and power module or resistor openings. Be sure to use all of the water in each container.
19. Install the blower motor Blower Motor - Installation.
20. Install the blower motor resistor or power module, depending on application Blower Motor Resistor - Installation or Blower Motor Power Module - Installation.
21. Disconnect the wire harness connector from the A/C compressor to disable compressor operation A/C Compressor - Removal.
22. Start the engine
23. Adjust all the windows so they are open approximately 8 mm (0.5 in.).
24. Set the A/C-heater controls to the following:
- air distribution to Panel and Recirculation mode
- temperature to full heat

25. Allow the vehicle to run for 20 minutes.
26. Turn the engine off.
27. Raise and support the vehicle.
28. Inspect the evaporator drain hose or tube (depending on application) for foreign material that may have blocked the drain during evaporator coil cleaning and repair as necessary.
29. Once drain operation has been verified;
- when equipped with a rubber drain hose, temporarily pinch the drain hose closed using an appropriate pair of heater hose pliers.
- when equipped with a solid plastic drain tube, obtain an appropriate size rubber or plastic cap or plug and temporarily cap or plug the drain tube.

30. Lower the vehicle.
31. Remove the blower motor Blower Motor - Removal.
32. Remove the blower motor resistor or power module, depending on application Blower Motor Resistor - Removal or Blower Motor Power Module - Removal.
33. Using PSE Flex Spray Delivery Tool 534-62637 or equivalent, completely coat the entire surface of A/C evaporator with one bottle of Mopar(R) Cooling Coil Coating through the blower motor and power module or resistor openings. Be sure to use all of the coil coating in the container.

NOTE: Be sure to thoroughly clean out the spray delivery tool with warm water once coil coating is complete to prevent damage to the tool.

34. Refill the empty bottles with clean warm tap water and completely rinse out the PSE Flex Spray Delivery Tool 534-62637, or equivalent.
35. Allow the vehicle to sit for 30 minutes.
36. Install the blower motor Blower Motor - Installation.
37. Install the blower motor resistor or power module, depending on application Blower Motor Resistor - Installation or Blower Motor Power Module - Installation.
38. Raise and support the vehicle.

WARNING: Excess cooling coil coating will drain from the evaporator housing when the clamp, cap or plug is removed from the evaporator drain hose or tube. Always use eye protection, rubber gloves and protective clothing. Avoid continuous breathing of vapors from evaporator coil sealing fluid. Avoid contact with skin and eyes. Failure to follow these instruction may result in possible serious or fatal injury.

39. Remove the previously installed clamp, cap or plug from the evaporator drain hose or tube and allow excess coil coating to drain from the HVAC housing.
40. Lower the vehicle.
41. Start the engine
42. Adjust all the windows so they are open approximately 8 mm (0.5 in.).
43. Set the A/C-heater controls to the following:
- air distribution to Panel and Recirculation mode
- temperature to full heat

44. Allow the vehicle to run for 20 minutes.
45. Turn vehicle off.
46. Remove protective cover from front passenger side floor and seat area.
47. Connect the wire harness connector to the A/C compressor A/C Compressor - Installation.
48. Verify proper A/C-heater system operation.