Cadillac 60 Series 1963 Shop Manual page 410

HEATING AND AIR CONDITIONING
13-29
2. Open valve 4 on Charging Station, J-8393,
to purge air from line.
3. Connect Charging Station high pressure line
to high pressure fitting on compressor, and low
pressure line to suction throttling valve.
4. With shift lever in "Park" position, start
engine and operate at 2000 rpm.
5. Move upper Air Conditioner control lever
to "Cool" position, lower lever to extreme left,
and fan switch to "High".
6. Close hood as far as possible without pinch-
ing lines. Use masking tape to cover gap at rear
of hood.
7. Place auxiliary fan (approximately 24 inch
dia. blades) thirty inches from front bumper and
direct air stream to center of radiator grille.
NOTE: Volume must be sufficient to obtain
proper head and return pressures.
8. Place accurate thermometer in right hand
air conditioner outlet grille. Thermometer bulb
must not contact any metal.
9. Place another thermometer in air stream
between auxiliary fan and radiator grille. Ther-
mometer bulb must not contact any metal.
10. Use Humidicator, J-6076, to obtain sim-
ultaneous temperature and humidity readings of
air entering cowl intake grille as described below:
a. Shake thermometers down to settle red and
blue columns in bottom of tubes.
b. Place Humidicator on right hand cowl air
intake grille so that entering air passes over
bulbs of thermometers. Thoroughly moisten wick
on blue thermometer with water.
c. After five minutes, record red and blue bulb
reading.
d. To determine relative humidity of air
entering cowl intake, position inner scale of
humidicator calculator so that wet bulb (blue)
temperature is opposite dry bulb (red) tempera-
ture. Relative humidity will appear opposite
Humidity arrow. Record humidity reading.
11. Record following readings: temperature of
air entering cowl air intake grille, temperature of
air discharged from right hand Air Conditioner
outlet, temperature of air entering radiator grille,
head pressure, and suction throttling valve pres-
sure.
12. Refer to Fig. 13-24, Chart A, to determine
if outlet air temperature is normal. (Use Chart
C for 75 series cars.) If outlet temperature is
the same or below reading on chart, operation is
normal.
13. Refer to Fig. 13-24, Chart B, to determine
if head pressure is normal. (Use Chart D for
75 series cars.) If head pressure is within 30
pounds below reading on chart, operation is
normal.
NOTE: If head pressure is abnormal, check
suction throttling valve setting as described in
Note 47a, or 47b for 75 series cars.
14. On 75 series cars, it is also necessary to
check operation of rear unit as follows:
a. Place accurate thermometer in right hand
roof duct grille and another thermometer over
return air intake at center of package shelf.
b. Close off rear unit outside air intakes.
NOTE:
closed.
Doors and windows should still be
c. After five minutes, read outlet and return
air temperatures. Outlet air temperature must
be at least 19°F lower than return air temper-
ature.
NOTE: Make certain that access plate on
rear evaporator assembly is in place before
taking outlet and return air temperature read-
ings. Otherwise, incorrect temperature read-
ings will result.
15. Shut off engine and disconnect Charging
Station.
19. Purging Refrigerant
From System
In replacing any Air Conditioner component,
the system must be purged (drained) of refrig-
erant. The purpose is to lower pressure inside
system so that a component part can be safely
removed. Following is a simplified procedure
for purging refrigerant from system.
CAUTION: Always wear goggles when doing
work that involves opening refrigerant lines.
1. Remove caps from high and low pressure
fittings on compressor.
2. Install Gage Adapters, J-5420, on compres-
sor high and low pressure fittings.
3. Tighten adapters to depress valve cores
until a hissing sound is heard, indicating that
refrigerant is escaping from system at each adap-
ter.
NOTE: Do not overtighten adapters; other-
wise, oil will escape from system. Refrigerant
should escape in a vaporous form. If any trace
of oil is detected, loosen adapters.