This air conditioning compressor is a 12V unit that circulates refrigerant through the tractor cabin's climate control loop. It is a 10S15C type compressor, which uses a swash-plate design to draw low-pressure gas from the evaporator, compress it, and discharge high-pressure gas to the condenser. The compressor is driven by the engine via a belt and clutch assembly; the clutch engages when the cabin thermostat calls for cooling. A failing compressor typically results in insufficient cabin cooling or a seized pulley bearing that produces a chirping or grinding noise. The manufacturer supplies this unit with the correct oil charge of 180 ml, which matches the lubrication requirements of the internal swash-plate and shaft bearings. When replacing, transfer the clutch and pulley from the old unit if they are serviceable, and evacuate and recharge the system to the specified refrigerant weight.