12 - 9
Section B
Body & Framework
9803/6400
Section B
12 - 9
Issue 1
Air Conditioning
System Diagnosis
Normally Functioning A/C System
Gauge Readings:
Low Side Gauge - Normal.
High Side Gauge - Normal.
Other symptoms:
Sight Glass - Clear.
Discharge Air - Cold.
Normal gauge readings will depend on system components
and ambient conditions, make sure that the valves are closed
and the readings are stable and that the system has a full
charge.
The pressures on the manifold at 25 °C with the engine at
1500 RPM, the blower on maximum and the thermostat set to
maximum, should be approximately:
Typically, the high pressure is 6 - 8 times the low pressure.
LOW SIDE - 2.0 bar (2.0 kgf/cm
2
)(29 lbf/in
2
)
HIGH SIDE - 14.8 bar (15.1 kgf/cm
2
)(215 lbf/in
2
)
A High Pressure/Temperature
Gas.
B Low Pressure/Temperature
Gas.
C High Pressure Liquid.
CC
BB
AA
LOW SIDE (RED) HIGH SIDE (BLUE)
Normal Normal