Heating and Ventilation System
The heating and ventilation and blower units are standard on all models. Air conditioning system is an optional module, which when fitted provides fully integrated climate control for the vehicle interior.The heating and ventilation unit controls the air distribution and heating to the vehicle interior. The blower unit controls the volume of air supplied, while the air conditioning module (when fitted) provides refrigerated and dehumidified air.
Heating And Ventilation Distribution Unit:
1 Fresh air inlet
2 Recirculation air inlet
3 Air outlets screen de-mist
4 Air outlet face level vents
5 Air outlets front footwells
6 Air outlets to rear footwells
7 Fresh/recirculation air flap servo
8 Blower motor relay
9 Multiplug connector to main harness
10 Multiplug connector, blower to heater unit
11 Resistor unit - blower speed.
Through-flow ventilation
Through-flow ventilation is achieved by means of one-way air extraction vents incorporated in both rear quarter body panels. The vents open and close automatically dependent upon the heating and ventilation unit control settings and the volume of air entering the vehicle.
Heating and ventilation unit, controls
The Heating and Ventilation Unit is centrally located and concealed by the dash assembly. When air conditioning is fitted, an evaporator is mounted in the heater unit forward of the heater matrix.
The dash mounted central controls are used to operate both systems. A single switch controls the air conditioning unit when fitted.
Controls set for maximum heat to footwells and face level vents
Heating and ventilation flaps and air flow key
1 Fresh or recirculated air from blower unit
2 Evaporator matrix - air conditioning (when fitted)
3 Heater matrix
4 Air outlet front footwells
5 Air outlet to rear footwells
6 Air outlet face level vents
7 Air outlets screen de-mist
8 Control flap - face level vents
9 Control flap - demist vents
10 Control flap - air direction
11 Control flap - air temperature
12 Control flap - air direction
Controls set for maximum heat to footwells and face level vents
Heater and ventilation operation
The heating and ventilation system contains a heater matrix, which is connected to the engine cooling system, and a 4 speed fan for air distribution. Engine coolant is circulated through the heater matrix continuously, except when the temperature controls are set to COLD.
Recirculated air
When the recirculation switch is pressed, an electrical servo operates and fully closes the fresh air intake flap.
Fresh air
When the recirculation switch is returned to the OFF position, the electrical servo returns and fully opens the fresh air intake flap.
Heated air
Temperature output is controlled by the temperature controls which move the air direction and temperature flaps independently to increase or decrease the volume of air flow through the heater matrix.
V8 Engine: When both controls are in the cold position, the coolant valve is turned off.
Face level vent flap
Control at face level, flap fully open. All other vents closed.
Control at face and foot level, flaps half open.
Unless an air conditioning unit is fitted, only fresh or re-circulated air is available from the face level vents.
Demist vent flap
Control at demist, flap fully open. All other vents closed.
Control at demist and foot level, flaps half open.
Air direction flap
Flap moves across mixing chamber to direct the air flow away from the heater matrix.
Air temperature flap
Control at HOT, flaps fully closed. All air flow passes through heater matrix. As control is moved towards COLD the flaps progressively open directing air flow away from the heater matrix. Control at COLD, flaps fully open.
V8 Engine: When both controls are at COLD, 2 micro-switches are closed and operate a vacuum valve which closes the coolant valve.
Air conditioning
When an air conditioning unit is fitted, the mechanical operation of the heater controls remains unaltered. However the air conditioning evaporator is positioned in front of the mixing chamber through which all air flow passes.