set clock JEEP YJ 1995 Service And User Guide

EVAPORATOR COIL:The coil is located in the
A/C housing. Its function is to remove heat and de-
humidify the air before it enters the vehicle.
FIN SENSING CYCLING CLUTCH SWITCH:
The switch is attached to the evaporator coil with the
temperature sensing probe inserted into the coil fins.
This switch controls evaporator temperature and pre-
vents condensate water on the evaporator coil from
freezing. It does this by sending signals to the Pow-
ertrain Control Module (PCM) to cycling the com-
pressor clutch on and off. This switch is used onXJ
only.
FILTER-DRIER:The drier is used to remove any
traces of moisture from the refrigerant system. A
sight glass is located on top of the filter drier. It is
used as a diagnostic tool to observe refrigerant flow.
HIGH PRESSURE RELIEF VALVE:The valve is
located on the filter drier. The valve is used to pre-
vent excessive high pressure build of 3445 to 4135
kPa (500 to 600 psi) and above. This prevents dam-
age to the compressor and other system components.
LOW-PRESSURE HIGH-PRESSURE CUT-OFF
SWITCH:The switch is located on the filter drier
and is wired in series with compressor clutch. When
the pressure drops down to 193 kPa (28 psi) the
switch interrupts the power to the compressor clutch.
When the pressure increases above 3100 to 3375 kPa
(450 to 490 psi) the switch interrupts the power to
the compressor clutch.
THERMOSTAT:The thermostat is located in the
evaporator housing. The thermostat temperature
sensing probe is inserted into the evaporator coil. Its
function is to cycles the compressor clutch on and off.
This switch controls temperature and prevents con-
densate water on the evaporator coil from freezing.
The thermostat is used on theYJonly.
REFRIGERANT LINES:The lines are used to
carry the refrigerant between the various system
components.
SERVICE PORTS:The high pressure service port
is located on the discharge line near the compressor.
The low pressure service port is located on the suc-
tion line near the compressor. These ports are used
to attach A/C gauges. After servicing the refrigerant
system, always install service port caps.
REFRIGERANT
XJ and YJ vehicles use a new type of refrigerant
called R-134a. It is a non-toxic, non-flammable, clear
color-less liquified gas.
R-134a refrigerant is not compatible with R-12 re-
frigerant. A small amount of R-12 in a R-134a system
will cause compressor failure, oil sludge or poor air
conditioning performance.R-134a refrigerant requires a special type of com-
pressor oil (SP20 PAG). When adding oil, make sure
that it is designed to be used in a R-134a system and
the SD7H15 compressor.
Service ports have been designed to ensure that
the system is not accidentally filled with R-12 refrig-
erant.
REFRIGERANT EQUIPMENT
WARNING: EYE PROTECTION MUST BE USED
WHEN SERVICING AN AIR CONDITIONING REFRIG-
ERANT SYSTEM. TURN OFF (ROTATE CLOCKWISE)
ALL VALVES ON THE EQUIPMENT BEING USED
BEFORE PROCEEDING WITH THIS OPERATION.
PERSONNEL INJURY CAN RESULT.
Chrysler Corporation recommends a (R-134a) recy-
cling device that meets SAE standard J2210 be used
when servicing the refrigerant system. Contact an
automotive service equipment supplier for refrigerant
recycling equipment that is available in your area.
Refer to the operating instructions provided with the
recycling equipment for proper operation.
MANIFOLD GAUGE SET
CAUTION: DO NOT use an R-12 manifold gauge set
on an R-134a system. The refrigerants are not com-
patible and system damage will result.
A manifold gauge set (Fig. 1) may be needed in
conjunction with the charging and or recovery/recy-
cling device. The service hoses on the gauge set being
used should have manual (turn wheel) or automatic
back flow valves at the service port connector ends.
This will prevent refrigerant from being release into
the atmosphere.
LOW PRESSURE GAUGE HOSE
The low pressure hose (BLUE with BLACK STRIP)
should be attached to the charging/service port. This
port is located at the right front of the engine com-
partment in the condenser-to-evaporator line.
HIGH PRESSURE GAUGE HOSE
The high pressure hose (RED with BLACK STRIP)
should be attached to the discharge/service port. This
port is located on the compressor plumbing or mani-
fold.
RECOVERY/RECYCLING/EVACUATION/
CHARGING HOSE
The center manifold hose (YELLOW or WHITE
with BLACK STRIP) is used to recover, evacuate and
charge the refrigerant system. When the low or high
pressure valves on the manifold gauge set are
opened, the refrigerant in the system will escape
through this hose.
JHEATING AND AIR CONDITIONING 24 - 7