GMC 1976 ZEO 6083 Maintenance Manual page 70

tem and the refrigerant and oil contained in the sys-
tem are designed to remain in a state of chemical
stability as long as pure R-12 and uncontaminated
refrigeration oil is used in the system .
However, when abnormal amounts of foreign
materials, such as dirt, air or moisture are allowed to
enter the system, the chemical stability may be upset.
When accelerated by heat, these contaminants may
form acids and sludge and eventually cause the
breakdown of components within the system . In ad-
dition, contaminants may affect the temperature-
pressure relationship of R-12, resulting in improper
operating temperature and pressures and decreased
efficiency of the system .
The following general practices should be ob-
served to ensure chemical stability in the system :
1 . Whenever it becomes necessary to disconnect
a refrigerant or gauge line, it should be immediately
capped . Capping the tubing will also prevent dirt and
foreign matter from entering .
2. Tools should be kept clean and dry. This also
includes the gauge set and replacement parts.
3. When adding oil, the container should be ex-
ceptionally clean and dry due to the fact that the
refrigeration oil in the container is as moisture-free
as it is possible to make it ; therefore, it will quickly
absorb any moisture with which it comes in contact.
For this same reason the oil container should not be
opened until ready for use and then it should be
capped immediately after use.
4. When it is necessary to open a system, have
everything you will need ready and handy so that as
little time as possible will be required to perform the
operation. Don't leave the system open any longer
than is necessary.
5 . Finally, after the operation has been completed
and the system sealed again, air and moisture should
be evacuated from the system before recharging .
CHARGING STATION J-24410
This portable air conditioner service station (fig-
ure 26) features the new J-24364 High Capacity
Vacuum Pump . Utilization of J-24364 enables the
J-24410 service station to out-perform all competi-
tive stations in the automotive field today .
The capacity of the J-24364 is three cubic feet per
minute; four times that of the J-5428-03 which
pumps at a rate of .8 cubic feet per minute . A vented
exhaust aids in the removal of moisture at a much
faster rate .
AIR CONDITIONING SYSTEM 1- 5 3
With the added increases in capacity the new
J-24410 will enable a serviceman to perform the
evacuation procedure in an automotive air condi
tioning system in one third less time . This of course
is a money saving feature.
The J-24410 incorporates two compound gauges .
The second compound gauge is used to permit
checking of other Motor Home manufacturer's sys
tems at the evaporator pressure release valve . The
CMN fast flow manifold incorporates a new O ring
stem which permits the manifold to be opened or
closed in two and a half turns.
This station is equipped with a controlled heated
cylinder which assures a complete charge into the
high pressure side of the compressor . This feature
reduces the charging time considerably and enables
a complete and accurately measured charge without
running the engine!
The line from the manifold to the pump is 3/8"
I.D . copper tube which is a larger I.D . for less re-
striction on pull down . The cylinder is graduated for
Refrigerant-12 and Refrigerant-22 . Refrigerant-22 is
used in some of the refrigerant systems on recrea-
tional vehicles . Also the cylinder has a heating ele-
Figure 26-Charging Station J-24410