Isuzu 1999 RODEO Workshop Manual page 78

1A–50 HEATING, VENTILATION AND AIR CONDITIONING (HVAC)
3. Connect the low pressure charging hose of the
manifold gauge to the low pressure side service valve
of the vehicle.
4. Connect the high pressure charging hose of the
manifold gauge to the high pressure side service
valve of the vehicle.
Legend
(1) Low Side
(2) High Side
(3) Refrigerant Container
(4) Weight Scale
5. Place the refrigerant container(3) up right on a weight
scale(4).
Note the total weight before charging the refrigerant.
a. Open the refrigerant container valve.
b. Open the low side vale on the manifold gauge set.
Refer to the manufacturer's instructions for a
weight scale charging station.
6. Perform a system leak test:
f Charge the system with approximately 200 g
(0.44 lbs) of HFC-134a.
f Make sure the high pressure valve of the manifold
gauge is closed.
f Check to ensure that the degree of pressure does
not change.
f Check for refrigerant leaks by using a HFC-134a
leak detector.
f If a leak occurs, recover the refrigerant. Repair the
leak and start all over again from the first step of
evacuation.
7. If no leaks are found, continue charging refrigerant to
the air conditioning system.
f Charge the refrigerant until the scale reading
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decreases by the amount of the charge specified.
Specified amount: 650 g (1.43 lbs)
f If charging the system becomes difficult:
1. Run the engine at idle and close all the vehicle
doors.
2. Turn A/C switch "ON".
3. Set the fan switch to its highest position.
4. Set the air source selector lever to "CIRC".
5. Slowly open the low side valve on the manifold
gauge set.
WARNING: BE ABSOLUTELY SURE NOT TO OPEN
THE HIGH PRESSURE VALVE OF THE MANIFOLD
GAUGE. SHOULD THE HIGH PRESSURE VALVE BE
OPENED, THE HIGH PRESSURE REFRIGERANT
WOULD FLOW BACKWARD, AND THIS MAY CAUSE
THE REFRIGERANT CONTAINER TO BURST.
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