REFRIGERATION SYSTEM
ATC-15
C
D
E
F
G
H
I
K
L
MA
B
AT C
REFRIGERATION SYSTEMPFP:KA990
Refrigerant CycleEJS001Z0
REFRIGERANT FLOW
The refrigerant flows in the standard pattern, that is, through the compressor, the condenser with liquid tank,
through the evaporator, and back to the compressor. The refrigerant evaporation through the evaporator coil is
controlled by an externally equalized expansion valve, located inside the evaporator case.
FREEZE PROTECTION
Under usual operating conditions, when the A/C is switched on, the compressor runs continuously, and the
evaporator pressure, and therefore, temperature is controlled by the CSV613 displacement compressor to
prevent freeze up.
Refrigerant System ProtectionEJS001Z1
REFRIGERANT PRESSURE SENSOR (WITH GASOLINE ENGINE)
The refrigerant system is protected against excessively high or low pressures by the refrigerant pressure sen-
sor, located on the liquid tank. If the system pressure rises above, or falls below the specifications, the refriger-
ant pressure sensor detects the pressure inside the refrigerant line and sends the voltage signal to the ECM.
ECM makes the A/C relay go OFF and stops the compressor when pressure on the high pressure side
detected by refrigerant pressure sensor is over about 2,746 kPa (27.5 bar, 28 kg/cm
2 , 398 psi), or below
about 134 kPa (1.37 bar, 1.4 kg/cm
2 , 20 psi).
DUAL-PRESSURE SWITCH (WITH DIESEL ENGINE)
The refrigerant system is protected against excessively high or low pressures by the dual-pressure switch,
located on the liquid tank. If the system pressure rises above or falls below the specifications, the dual-pres-
sure switch opens to interrupt the compressor operation.
PRESSURE RELIEF VALVE
The refrigerant system is also protected by a pressure relief valve, located in the rear head of the compressor.
When the pressure of refrigerant in the system increases to an unusual level [more than 3,727 kPa (37.3 bar,
38 kg/cm
2 , 540 psi)], the release port on the pressure relief valve automatically opens and releases refriger-
ant into the atmosphere.
RHA682H