Mazda 6 Training Manual page 328

Evaporator
• The double-tank drawn cup is the same as the previous model ecept that a new refrigerant flow pattern has
been adopted. Due to this, size and weight reduction is achieved while maintaining performance.
Epansion Valve
• The epansion valve causes a sudden decrease in the pressure of the liquid refrigerant. This atomizes the
refrigerant, making it easier for the evaporator to vaporize it. The epansion valve also regulates the flow
volume of the refrigerant sent to the evaporator.
• The amount of refrigerant delivered to the evaporator is adjusted by the opening angle of the ball valve in the
epansion valve.
• Opening angle is adjusted by a balance of the R-134a pressure (Pb) in the diaphragm, and a composite force
of evaporator discharge pressure (PI) against the lower part of the diaphragm and spring force (Fs) pushing up
the ball valve. When PI increases, the temperature of the temperature sensor near the diaphragm rises and the
Pd heated by the R-134a in the diaphragm increases. When the Pd increases more than PI + Fs, the
diaphragm is pushed down, and the shaft attached to end of the temperature sensor rod pushes down the ball
valve, increasing the amount of liquid refrigerant flow. When the evaporator discharge refrigerant temperature
decreases, PI + Fs increases more than Pd, the ball valve is pushed up, and the amount of liquid refrigerant
flow decreases.
.
1 Diaphragm
2 Temperature sensor
3 Shaft
4 Ball valve
5 Spring
6 From evaporator
BASIC SYSTEM
7 To evaporator
8 From condenser
9 To condenser
10 Spring force
11 HFC-134a pressure
12 Discharge pressure
A6E8516T007
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A6E8516T003
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