Heating and Ventilation Controls

Heating and Ventilation Controls

1 Distribution control knob 2 Blower fan speed control knob 3 Temperature control knob

4 Fresh/recirculated air selection switch 5 Air conditioning selection switch (where fitted)

Rotary knobs are installed on the centre console to control air distribution, blower speed and air temperature. The air distribution and temperature knobs operate cables connected to the control flaps in the heater assembly. The blower speed knob operates a rotary switch in the blower's electrical circuit. Graphics on the control panel indicate the function and operating positions of the controls.

Fuel Burning Heater (FBH) System (Where Fitted)

The FBH system is an auxiliary heating system that compensates for the relatively low coolant temperatures inherent in the diesel engine. At low ambient temperatures, the FBH system heats the coolant supply to the heater assembly, and maintains it within the temperature range required for good in-car heating performance. Operation is fully automatic, with no intervention required by the driver.

The system consists of an ambient air temperature sensor, a FBH fuel pump and a FBH unit. Fuel for the FBH system is taken from the vehicle fuel tank, through a line attached to the fuel tank's fuel pump, and supplied via the FBH fuel pump to the FBH unit. The connection on the fuel tank's fuel pump incorporates a tube which extends down into the tank. In the FBH unit, the fuel delivered by the FBH fuel pump is burned and the resultant heat output is used to heat the coolant. An ECU integrated into the FBH unit controls the operation of the system at one of two heat output levels, 5 kW at full load (i.e. maximum output) and 2.5 kW at part load.