CAB A N D BODY M OUNTINGS 1-61
SPECIAL
GAUGE
VALVE
(LOW PRESSURE)
THROTTLING VALVE
PRESSURE HOSE
SUCTION
LOW
REMOTE BULB AND
TUBING
C O N D EN SER
\
HIGH PRESSURE
REFRIGERANT
LOW
PRESSURE
REFRIGERANT
HIGH PRESSURE H O SE
Figure 6— Schematic of Refrigerant Cycle
poisonous gas. The same gas will attack all bright
metal surfaces.
D O N O T EX PO SE E Y E S T O R E F R IG E R A N T
One of the most important precautions is pro
tection of the eyes when handling refrigerant. Any
liquid refrigerant which may accidentally escape
is approximately 2 1 .7°F ., below zero. If any re
frigerant comes in contact with the eyes, serious
injury could result. Always wear goggles to pro
tect the eyes when handling refrigerant.
If refrigerant should come in contact with the
eyes:
1. D O N O T rub the eyes. Splash the eyes with cold
water to gradually get the temperature above
the freezing point.
2. Apply a protective film of an antiseptic oil over
the eye-ball to reduce the possibility of infection.
3. Consult a doctor or an eye specialist imm ed
iately.
Should liquid refrigerant come in contact with
the skin, the injury should be treated the same as
though the skin had been frostbitten or frozen.
REFRIGERANT CIRCULATION
Refrigerant control units and piping is illus
trated in figures 1 and 6. A complete cycle of the
refrigerating system is as follows*.
1. Refrigerant in its gaseous state is drawn
into the compressor where it is compressed and
discharged into the condenser,
2. As the heated gas circulates through the
condenser coils, it is cooled by air being forced
through the condenser by an engine cooling fan. The
combined effects of the decreased temperature and
increasing pressure cause the gas to condense
(liquify).
3. The liquid refrigerant is then forced from
condenser into the liquid receiver.
4. By its own pressure, liquid refrigerant is
forced from liquid receiver-dehydrator through
the expansion valve and into the evaporator.
5. In the evaporator, where the pressure is
reduced, the liquid refrigerant evaporates, or
changes into its gaseous state. As the liquid evap
orates, heat is absorbed from the air passing
through the evaporator coils, thus the air is cooled.
6. Flow of refrigerant into the evaporator is
regulated by the expansion valve. The expansion
valve is actually a pressure reducing valve which
serves two purposes:
a. It maintains pressure on the liquid line.
b. It admits only the required amount of liquid
refrigerant into the evaporator, this requirement
being determined by the temperature of the gaseous
refrigerant at the evaporator outlet.
7. The low pressure refrigerant gas passes
CHEVROLET SERIES 70-80 H EAVY DUTY TRUCK SH O P M A N U A L
Summary of Contents for 70 1969 Series
Page 1: ...CHEVROLET HEAVY DUTY TRUCK SHOP MANUAL...
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Page 11: ...LUBRICATION 0 4 CHEVROLET SERIES 70 80 HEAVY DUTY TRUCK SHOP MANUAL...
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