GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 HUMMER 🢒 2003 🢒 H2 🢒 HVAC 🢒 Heating, Ventilation and Air Conditioning 🢒 Heater Core Replacement

Removal Procedure
  1. Remove the HVAC module assembly. Refer to HVAC Module Assembly Replacement .
  2. Remove the screws from the heater core cover.

    3. Object Number: 826718 Size: SH
  3. Remove the heater core cover (1) from the HVAC module assembly (2).

    4. Object Number: 826720 Size: SH
  4. Remove the heater core cowl gasket (1) from the heater core (2).

    5. Object Number: 826688 Size: SH
  5. Remove the heater core (1) from the HVAC module assembly (2).

Installation Procedure

    Object Number: 826688 Size: SH
  1. Install the heater core (1) to the HVAC module assembly (2).

    2. Object Number: 826720 Size: SH
  2. Install the heater core cowl gasket (1) to the HVAC module assembly (2).

    3. Object Number: 826718 Size: SH
  3. Install the heater core cover (1) to the HVAC module assembly (2).

    4. Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  4. Install the screws to the heater core cover (1).

    5. Tighten
    Tighten the screws to 2 N·m (18 lb in).

  5. Install the HVAC module assembly. Refer to HVAC Module Assembly Replacement .