Expansion valve, component description - GF83.40-P-2190G
MODEL 463.306 /336 /346 as of model year 2011 /YoM 10
MODEL 463.202 /222 /236 /237 as of model year 2009 /YoM 08
MODEL 463.247 /248 /249 /254 /270 /271 /303 /340 /341 as of model year 2007
Location
The expansion valve is located on the firewall.
Task
The expansion valve sprays liquid refrigerant into the evaporator. The injection quantity depends on the pressure and temperature of the refrigerant supplied.
Function
When the refrigerant compressor (A9) is switched on, the pressure in the evaporator decreases causing a diaphragm in the expansion valve to arch. The diaphragm motion is transferred to a linkage. The plunger presses the valve ball out of its seat opening the valve. The opened valve enables the refrigerant to be sprayed into the evaporator. Because the motion of the diaphragm depends on the suction pressure as well as the temperature at the evaporator outlet, only the quantity of refrigerant which can evaporate optimally is injected.