REFRIGERATION SYSTEM
ATC-15
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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