Air conditioning (Cooling unit): Description and operation

COOLING UNIT

The cooling unit directs the flow of air, from the plenum or the vehicle interior, through the evaporator to the heater assembly.

The cooling unit is installed in place of the air inlet duct of non air conditioned vehicles, and contains the evaporator, thermostatic expansion valve and thermostat. It also incorporates the water condensate drain and the fresh and recirculated air inlets. A control flap, operated by a recirculated air motor, opens and closes the fresh and recirculated air inlets. On the downstream side of the evaporator, the casings are lined with polstyrene insulation.

Cooling unit components (LH drive shown, RH drive similar)

1. Evaporator casing
2. Air intake
3. Recirculated air inlet
4. Control flap lever
5. Recirculated air motor
6. Water condensate drain hose
7. Wiring harness
8. Thermostat
9. Evaporator
10. Insulation