Chevrolet BEAUVILLE SPORTVAN G10 SERIES, Service Manual

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A IR C O N D IT IO N I IMG 1A 12
GENERAL INFORMATION
In any vocation or trad e, th e re are established procedures
and practices th a t have been developed after m any years o f
experience. In a d d itio n , occu p atio n hazards m ay be present
th a t require th e observation o f certain p recautions or use o f
special tools and eq u ip m en t. Observing th e procedures,
practices and p recautions o f servicing refrigeration equipm ent
will greatly reduce th e possibilities o f dam age to the
custom ers’ equ ip m en t as w ell as virtually elim inate the
elem ent o f hazard to th e servicem an.
PRECAUTIONS IN H A N D LIN G REFR IG ER A N T-12
R efrigerant—12 is tran sp a re n t and colorless in b o th the
gaseous and liquid state. It has a boiling poin t o f 2 1 .7°F below
zero an d , th erefo re, at all norm al tem peratures and pressures it
will be a vapor. The vapor is heavier th a n air and is non-
inflam m able, nonexplosive, nonpoisonous (except w hen in
c o n tac t w ith an open flam e) and noncorrosive (except w hen in
co n tac t w ith w ater).
W A R N IN G : The follow ing precautions in handling
R -1 2 should be observed at all times.
• I f it is ever necessary to tran sp o rt o r carry a cylinder or
can o f refrigerant in a car, keep it in th e luggage
co m p artm e n t. R efrigerant should n o t be exposed to the
rad ian t h eat from th e sun since th e resulting increase in
pressure m ay cause th e safety valve to release o r the
cylinder or can to burst.
• Cylinders or disposable cans should never be subjected to
high tem p eratu re w hen adding refrigerant to th e system .
In m ost instances, heating th e cylinder or can is required
to raise th e pressure in th e container higher th a n the
pressure in the system during the o peration. I t w ould be
unw ise to place th e cylinder on a gas stove, rad iato r or
use a blow to rc h while preparing fo r th e charging
o p era tio n , since a serious accident could result. D o n ’t
depend on the safety valve — m any cylinders have burst
w hen the safety valve failed. R em em ber, high pressure
m eans th a t great forces are being exerted against the
w alls o f th e container. A bu ck et o f w arm w ater, n o t over
125°F , or warm w et rags around th e con tain er is all the
h e a t th a t is required.
• D o n o t weld or steam clean on or near th e system.
W elding o r steam cleaning can result in a dangerous
pressure buildup in th e system .
• Discharging large q u an tities o f R -12 in to a room can
usually be done safely as th e vapor w ould produce no ill
effects; how ever, in th e event o f an accidental rapid
discharge o f the system , it is recom m ended th a t inhala­
tio n o f large quantities o f R -12 be avoided. This caution
is especially im p o rta n t if th e area contains a flame
producing device such as a gas heater. While R -12
n orm ally is nonpoisonous, heavy co ncentrations o f it in
c o n ta c t w ith a live flam e will produce a to x ic gas. The
sam e gas will also a tta c k all bright m etal surfaces.
• P ro tectio n o f th e eyes is o f vital im portance! When
w orking around a refrigerating system , an accident m ay
cause liquid refrigerant to h it th e face. I f th e eyes are
p ro te c te d w ith goggles or glasses, no serious damage can
result. Ju st rem em ber, any R-12 liquid th a t you can
to u c h or th a t to u ch es yo u is a t least 21.7UF, below zero.
I f a R -12 liquid should strike th e eyes, here is w hat to
d o :
1. K eep calm.
2. Do n o t rub the eyes! Splash th e affected area w ith
q uantities o f cold w ater to gradually get th e tem p eratu re
above th e freezing p o in t. The use o f m ineral, cod liver or
an antiseptic oil is im p o rta n t in providing a protective
film to reduce the possibility o f infection.
3. As soon as possible, call or consult an eye specialist for
im m ediate and fu tu re trea tm e n t.
PRECAUTIONS IN H A N D LIN G
R E FR IG E R A N T LINES
C A U T IO N : The follow ing precautions should be
observed when handling refrigerant lines:
• All m etal tubing lines should be free o f kinks, because o f
th e restriction th a t kinks will offer to th e flow o f
refrigerant. The refrigeration capacity o f th e entire
system can be greatly reduced by a single kink.
• The flexible hose lines should never be b e n t to a radius
o f less than 10 tim es the diam eter o f th e hose.
• The flexible hose lines should never be allowed to com e
w ithin a distance o f 2 -1 /2 ” o f the exhaust m anifold.
• Flexible hose lines should be inspected a t least once a
year for leaks or brittleness. I f fo u n d brittle o r leaking
th e y should be replaced w ith new lines.
• Use only new lines th a t have been sealed during storing.
• W hen disconnecting any fitting in the refrigeration
system , the system m ust first be discharged o f all
refrigerant. H ow ever, proceed very cautiously regardless
Fig. 1 9 —System Contam inants
C H E V Y V A N S H O P M A N U A L