Heater Core: Service and Repair

Replacement

1. Disconnect the negative (-) battery terminal.
2. Recover the refrigerant with a recovery/ recycling/ charging station.
3. When the engine is cool, drain the engine coolant from the radiator.

4. Remove the heater & blower assembly.

5. Remove the blower unit (B) from heater unit after loosening 3 screws.








6. Loosen the mounting screw and then remove the heater core cover (A).




7. Remove the heater core (A) from heater unit.





NOTE:
- Be careful that the inlet and outlet pipe are not bent during heater core removal / installation.

8. Installation is the reverse order of removal

NOTE:
- If you're installing a new evaporator, add refrigerant oil (ND-OIL8).
- Replace the O-rings with new ones at each fitting, and apply a thin coat of refrigerant oil before installing them. Be sure to use the right O-rings for R-134a to avoid leakage.
- Immediately after using the oil, replace the cap on the container, and seal it to avoid moisture absorption.
- Do not spill the refrigerant oil on the vehicle ; it may damage the paint ; if the refrigerant oil contacts the paint, wash it off immediately
- Apply sealant to the grommets.
- Make sure that there is no air leakage.
- Charge the system and test its performance.
- Do not interchange the inlet and outlet heater hoses and install the hose clamps securely.
- Refill the cooling system with engine coolant