Hudson 1955 Rambler, Техническое и сервисное руководство

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ALL SEASON AIR CONDITIONING SYSTEM 19
CORRECT HANDLING OF FREON
Use safety glasses to protect eyes as —21.7°F.,
the boiling point of Freon-12, is a temperature
the eyes cannot normally stand. Treat for frost-
bite if either the eyes or portions of the body
are affected. Splash with cold water to raise
temperature of affected portion.
Always cap Freon-12 drum when not in use to
protect the valve and safety plug from damage.
The drum should never be carried in the
passenger compartment. Never leave the drum
exposed to sun light or high temperatures. The
drums are normally filled from 75 to 80 percent of
their capacity to allow for expansion. If the
occasion ever arises to fill small drums from a
large drum never fill completely. A full drum will
develop hydraulic pressure with a rise in temper-
ature.
Always weigh the cylinder before and after
charging to determine the amount of refrigerant in
the cylinder.
The drum should never be subjected to high
temperature when adding refrigerant to the system.
In most cases, heating the drum is required to
raise the drum pressure higher than the pressure
in the system during the operation. A container of
hot water (125°F.) is all the heat that is
required. Hot rags also will suffice. Never use a
blow torch or heat the drum on a stove or radiator.
Never discharge the system in an area where an
open flame is present. Freon-12 will not produce
toxic effects except when combined with a flame,
then poisonous gas will result. Freon vapor will
also damage the bright metal surfaces of the car.
Never inhale large quantities of Freon vapor as it
will act as an anesthetic.
Never permit a cylinder to be dropped or strike
another cylinder violently.
Handling of Lines
It is extremely important that the refrigerant
lines be kept dry and clean. Whenever a connection
is to be broken, clean all dirt and grease from
the connection.
Parts from stock are capped and dehydrated; the
caps should be removed only prior to installation.
Lines removed from the system to be used again
should be capped immediately to prevent dirt and
moisture from entering the line. If caps are not
available, copper lines can be placed in an oven
for a period of two or three hours before again
installing in the system. Bake at 275° to 300°F.
The same is possible with units in the system,
such as the evaporator core, condenser, compres-
sor, filter, receiver, and sight glass. The
expansion valve can be baked at 100° to 125°F. for
two to three hours. This process will insure
against moisture in these items. The rubber lines
should be baked at 200° F. for two hours.
The lines should be free of kinks that will
cause re-
cause restrictions to the flow of refrigerant.
The lines should be carefully stored to avoid
crushing or bending.
The proper size wrenches should be used in
tightening fittings. Always use two wrenches
when tightening fittings to prevent twisting the
soft copper tubing. Tubing that is left free to
vibrate will harden and crystallize the area of
the tube at the flare section so that it may
become brittle and break (Fig. 23).
FIGURE 23— Proper Method of Breaking
a Connection
Gauge set and lines should be kept clean and
free of moisture. Always plug when not in use.
The compressor lubricant container must not
be left open longer than necessary as the
special oil is moisture free and will absorb
moisture from the air if left uncapped.
PRESSURE GAUGE SET
The Gauge Manifold Set, Tool J-5725, is a
multipurpose tool and can be used to advantage
in servicing the system. In addition to being
used in charging a system, it can be helpful in
diagnosis of the system (Fig. 24).
A compound gauge that reads from 0 to 150
pounds pressure and 0 to 30 inches vacuum is on
the left hand side of the manifold. This gauge
is used to read pressures for the low pressure
side of the system and vacuum when used for
evacuation. The compound gauge will have its
gauge pointer at 0 when at atmospheric pressure
or room temperature; the pointer can move in
either direction along the scale from 0 depend-
ing on which use it is put to. The low pressure
side should never drop below approximately 10
pounds pressure when the system is functioning
properly. However, ab-