Workshop Manuals Factory service & repair Alfa Romeo
Alfa Romeo 145/146 Factory Service Manual (1994-1999)10 · Heating and ventilation
10 · Heating & A/C

Operating logic

Make
Alfa Romeo
Model
145/146 Factory Service Manual
Year
1994–1999
Section
Automatic heating and ventilation › Operating logic
Heating and ventilationOperating logic

OPERATING LOGIC

A special control unit manages automatic operation of the system controlling the thermodynamic parameters in order to provide the climatic comfort (temperature and humidity) required by the occupants of the vehicle.

According to the requests received and the temperature conditions detected, the control unit sets certain functions to adapt the temperature of the passenger compartment to the one required.

Block diagram: the control panel (TR), outside temperature (Te), passenger compartment temperature (Ta), treated air temperature (Tt) and antifrost sensor (Sa) feed the ECU, which controls MAX DEF, RIC and A/C and sets the temperature of air sent to the passenger compartment and the flow of air sent to the passenger compartment
ECUelectronic control unit
Teoutside temperature
Tapassenger compartment temperature
Tttreated air temperature
TRrequired temperature
RICrecirculation function
Saantifrost sensor
A/Ccompressor engagement

Through suitable control logics of the sensors and adjustment with "self-teaching" of the actuators, the electronic control unit is capable of recording and memorising a series of faults and failures that may occur in the system.

If these faults occur, the control unit still continues to manage system operation replacing any abnormal values with suitable "recovery" values which ensure minimal operation though not perfect of the system. For further information, see "ELECTRIC - ELECTRONIC DIAGNOSIS".

Parts & tools for this job For 1994 Alfa Romeo 145/146

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