GF83.40-P-2005G Automatic Air Conditioning Refrigerant Circuit, Function

GF83.40-P-2005G Automatic Air Conditioning Refrigerant Circuit, Function
MODEL 463.306 /336 /346 up to 31.5.12 as of model year 2011 /YoM 10
MODEL 463.202 /222 /236 /237 up to 31.5.12 as of model year 2009 /YoM 08
MODEL 463.247 /248 /249 /254 /270 /271 /303 /340 /341 up to 31.5.12 as of model year 2007





1 Capacitor
2 Fluid reservoir
3 Expansion valve
4 Front evaporator
5 Rear evaporator (with code (HH7) Additional air conditioning in rear)
A9 Refrigerant compressor
B10/6 Evaporator temperature sensor
B10/11 Rear air conditioning evaporator temperature sensor (with code (HH7) Additional air conditioning in rear)
B12/2 Refrigerant pressure and temperature sensor
Y67 Rear air conditioning refrigerant shutoff valve (with code (HH7) Additional air conditioning in rear)
A High pressure, gaseous
B High pressure, liquid
C Suction pressure, liquid
D Suction pressure, gaseous

Function
The refrigerant compressor driven by the engine compresses the gaseous refrigerant which heats up in the process. The compressed refrigerant flows through the condenser.
The refrigerant's compression heat is then withdrawn on the surface of the condenser. The refrigerant liquefies during cooling. If cooling by the airstream is not sufficient, the additional fan (M4) is activated and thus air is additionally drawn in to cool the condenser.
When the refrigerant flows through the fluid reservoir it is cleansed of any chemical and mechanical impurities.
The liquid refrigerant passes through the expansion valve into the front evaporator located in the fresh air flow.
In vehicles with code (HH7) Additional air conditioning in rear, refrigerant flows additionally through the rear evaporator when the rear air conditioning refrigerant shutoff valve is open. The rear air conditioning refrigerant shutoff valve is actuated by means of a direct line via the rear air conditioning control unit (N22/4) when cooling is needed.
Due to the evaporation process of the refrigerant starting in the evaporator, heat is removed from the air blowing by through the pipe and honeycomb system from the outside, thus cooling the air.
The air humidity carried along condenses and is led to the outside.
The air is thus dried.
The refrigerant compressor aspirates the refrigerant which has turned gaseous on account of the heat absorption and then compresses it yet again.
In the process, the pressure and refrigerant temperature sensor monitors the pressure and temperature of the refrigerant.
To prevent the evaporator from icing up, the refrigerant compressor is switched off by the AAC [KLA] control and operating unit (N22) when the temperature on the front evaporator drops below a certain value, or by the rear air conditioning control unit when the temperature on the rear evaporator drops below a certain value.