With Air Conditioning

Air Flow - A/C And Heater (typical):

TXV A/C System:

GENERAL DESCRIPTION
Passenger compartment comfort is maintained by the mix of cooled ambient air and heated air as controlled by the temperature lever on the instrument panel.

The A/C system uses the V-5 Variable Displacement compressor along with a Thermal Expansion Valve (TXV) as a flow control device.

THE VARIABLE DISPLACEMENT - THERMAL EXPANSION VALVE REFRIGERANT SYSTEM
The Variable Displacement Thermal Expansion Valve Refrigerant system employs the constant run V-5 compressor. The V-5 is a variable displacement compressor that can match the automotive air conditioning demand under all conditions without cycling.

The basic compressor mechanism is a variable angle wobble-plate with 5 axially oriented cylinders. The center of control of the compressor displacement is a bellows actuated control valve located in the rear head of the compressor that senses compressor suction pressure. The wobble-plate angle and compressor displacement are controlled by the crankcase-suction pressure differential.

When the A/C capacity demand is high, the suction pressure will be above the control point; the valve will maintain a bleed from crankcase to suction; no crankcase-suction pressure differential; and the compressor will have maximum displacement.

When the A/C capacity demand is lower and the suction pressure reaches the control point, the valve will bleed discharge gas into the crankcase and dose off a passage from the crankcase to the suction plenum. The angle of the wobble-plate is controlled by a force balance on the 5 pistons. A slight elevation of the crankcase-suction pressure differential creates a total force on the pistons resulting in a movement about the wobble-plate pivot pin that reduces the plate angle.