GF83.50-D-3008H Rear Air Conditioning Refrigerant Shutoff Valve, Component Description

GF83.50-D-3008H Rear Air Conditioning Refrigerant Shutoff Valve, Component Description

- with CODE (HH7) Additional air conditioning in rear







A32/2 Rear automatic air conditioning recirculation unit
A32/2y1 Refrigerant shutoff valve

Location
The refrigerant shutoff valve with the integrated rear expansion valve is located in the feed and return line of the rear air conditioning in the rear automatic air conditioning recirculation unit.

Task
The refrigerant shutoff valve with the integrated rear expansion valve regulates the flow of refrigerant to the rear evaporator depending on the low pressure (gaseous) and the temperature at the rear evaporator outlet. In addition, it interrupts the flow of refrigerant to the rear evaporator when actuated by the KLA control and operating unit (S98).







Rear expansion valve, design
26 Diaphragm
27 Aluminum housing
28 Control valve
29 Ball
30 Spring

Refrigerant shutoff valve with integrated rear expansion valve, function
The refrigerant shutoff valve with integrated rear expansion valve interrupts the flow of refrigerant to the rear evaporator if the rear automatic air conditioning is switched off using the rear air conditioning button (S98s7) integrated into the KLA control and operating unit or if the refrigerant compressor (A9) is switched off using the AC OFF and residual heat system button (S98s4) integrated into the KLA control and operating unit.
The KLA control and operating unit actuates the refrigerant shutoff valve with the integrated rear expansion valve and reduces the pulse width modulation (PWM) signal for the refrigerant compressor control valve (A9y1) to the refrigerant compressor.

Rear expansion valve, function
When switching on the refrigerant compressor, suction pressure is reduced in the line leading from the rear evaporator to the refrigerant compressor. This causes the diaphragm to bend downward. The control valve follows the diaphragm movement and pushes the ball against the spring out of its seating.
This in turn enables more refrigerant to flow into the rear evaporator via the refrigerant shutoff valve with the integrated rear expansion valve. More refrigerant evaporates in the evaporator and the suction pressure increases in the line leading from the rear evaporator to the refrigerant compressor. This causes the diaphragm to bend upward.
The control valve follows the diaphragm movement and the spring force pushes the ball back onto its seating. As a consequence, the refrigerant shutoff valve with the integrated rear expansion valve enables less refrigerant to flow into the rear evaporator. Less refrigerant now evaporates in the evaporator and the suction pressure decreases in the line leading from the rear evaporator to the refrigerant compressor.
The flow of refrigerant to the rear evaporator is regulated by the refrigerant shutoff valve with the integrated rear expansion valve. The movement of the diaphragm depends both on the suction pressure and the temperature at the rear evaporator outlet. Only the amount of refrigerant that can evaporate optimally flows.