Subaru LEGACY 2002 Quick Reference Index page 487

2. FUNCTIONS
As the rotor rotates, the volume of each cylinder chamber changes. This creates the compressor's
suction, compression and discharge functions as explained in the following:
1) Suction:
Low-pressure gaseous refrigerant is forced out from the evaporator by rotation of the compressor.
It enters the low-pressure chamber in the rear head through the check valve. The refrigerant is
then drawn into the cylinder by rotation of the vane-fitted rotor through the two suction ports pro-
vided in the rear side block. Air tightness of the cylinder chambers is maintained by the compres-
sor oil.
(1) Rotor
(2) Refrigerant
(3) Check valve
2) Compression:
Further rotation of the rotor after suction makes the volume of each cylinder chamber smaller, thus
compression occurs.
(1) Drive shaft
COMPRESSOR
(4) Rear head
(5) Low-pressure chamber
(6) Rear side block
(2) Refrigerant
AC-15
HVAC System (Heater, Ventilator and A/C)
(7) Vane
(8) Drive shaft
B4H0745A
B4H0746A