CORE-HEATER
DESCRIPTION
NOTE: LHD model shown. RHD model similar.
The heater core (1) for the heating-A/C system is mounted within the HVAC air distribution housing, which is located behind the instrument panel. The heater core is a heat exchanger made of rows of tubes with fins and is positioned within the air distribution housing so that only the selected amount of air entering the housing passes through the heater core before it is distributed through the heating-A/C system ducts and outlets. One end of the heater core is fitted with a tank (2) that includes the fittings for the heater core tubes (3).
The heater core can only be serviced by removing the HVAC housing from the vehicle.
OPERATION
Engine coolant is circulated through the heater hoses to the heater core at all times. As the coolant flows through the heater core, heat is removed from the engine and is transferred to the heater core tubes and fins. Air directed through the heater core picks up the heat from the heater core fins. The blend-air door allows control of the heater output air temperature by regulating the amount of air flowing through the heater core. The blower motor speed controls the volume of air flowing through the HVAC housing.
The heater core cannot be repaired and it must be replaced if found inoperative or damaged.
REMOVAL
NOTE: The HVAC housing assembly must be removed from vehicle for service of the heater core.
NOTE: LHD model with A/C shown. RHD and heater-only models similar.
1. Remove the HVAC housing assembly and place it on a workbench (refer to 24 - HEATING & AIR CONDITIONING/DISTRIBUTION /HOUSING-HVAC - HOUSING-HVAC ASSEMBLY - REMOVAL).
2. Remove the left side front floor duct (refer to 24 - HEATING & AIR CONDITIONING/DISTRIBUTION/DUCTS-FLOOR DISTRIBUTION - REMOVAL).
NOTE: If the foam seal for the flange is deformed or damaged, it must be replaced.
3. Remove the foam seal (1) from the flange (2) located on the front of the HVAC housing (9).
4. Remove the screw (10) that secures the flange to the front of the HVAC housing and remove the flange.
5. Remove the screw (3) that secures the retaining bracket (4) for the heater core tubes (8) to the left side of the air distribution housing (5).
6. On RHD models, remove the air distribution housing from the HVAC housing (refer to 24 - HEATING & AIR CONDITIONING/DISTRIBUTION/HOUSING-HVAC - HOUSING-AIR DISTRIBUTION - REMOVAL)
7. Carefully pull the heater core (6) out of the driver side of the air distribution housing.
INSTALLATION
NOTE: LHD model with A/C shown. RHD and heater-only models similar.
1. Carefully install the heater core (6) into the left side of the air distribution housing (5).
2. On RHD models, install the air distribution housing (5) onto the HVAC housing (9) (refer to 24 - HEATING & AIR CONDITIONING/DISTRIBUTION/HOUSING-HVAC - HOUSING-AIR DISTRIBUTION - INSTALLATION).
3. Install the retaining bracket (4) and screw (3) that secure the heater core tubes (8). Tighten the screw to 1.2 N·m (10 in. lbs.)
4. Install the flange (2) that secures the heater core tubes to the front of the HVAC housing.
5. Install the screw (10) that secures the flange to the HVAC housing. Tighten the screw to 1.2 N·m (10 in. lbs.).
NOTE: If the foam seal for the flange is deformed or damaged, it must be replaced.
6. Install the foam seal (1) onto the flange.
7. Install the left side front floor duct (refer to 24 - HEATING & AIR CONDITIONING/DISTRIBUTION/DUCTS-FLOOR DISTRIBUTION - INSTALLATION).
NOTE: If the heater core is being replaced, flush the cooling system (refer to 7 - COOLING - STANDARD PROCEDURE - COOLING SYSTEM CLEANING/REVERSE FLUSHING).
8. Install the HVAC housing assembly (refer to 24 - HEATING & AIR CONDITIONING/DISTRIBUTION/HOUSING-HVAC - HOUSING-HVAC ASSEMBLY - INSTALLATION).