Performance Test; Performance Data; Charging The System; Checking System Operation - Chevrolet CHEVY VAN G10 SERIES Service Manual

Charging the System
1. O nly after evacuating as above, is system ready for
charging. N ote reading on sight glass o f charging cylinder.
I f it does n o t contain a sufficient am oun t o f refrigerant
for a full charge, fill to th e proper level.
2. W ith High and Low Pressure Valves (1 and 2) open, close
V acuum C ontrol Valve (3), tu rn off vacuum pum p, open
Refrigerant C ontrol Valve (4) and allow refrigerant to
enter system .
N O T E : If the charge w ill not transfer completely
from the station to the system, close the high
pressure valve at the gauge set, set the air con­
ditioning controls for cooling, check th at the engine
com partm ent is free fro m obstructions and start the
engine. Compressor operation w ill decrease low side
pressure in the system.
System is now charged and should be checked as outlined
below:

Checking System Operation

1. O perate system fo r a few m inutes at m axim um cooling,
high blow er speed and w ith engine operating at 2000
RPM (exhaust should be vented if inside).
2. When system is stabilized, th e pressure gauges on the
Charging S tation should read pressures corresponding to
valves listed under PERFORM ANCE DATA.
3. W hen correct system pressures are observed, check sight
glass to ensure th a t sight glass is clear (n o foam or
bubbles can be observed).
4. Feel outlet air distribution to ensure th a t cold air is being
distributed.
5. D isconnect gauge lines and cap fittings.
C A U T IO N : When removing gauge lines from f i t ­
tings, be sure to remove the adapters fro m the
fittings rather than
adapters.

PERFORMANCE TEST

U nder norm al circum stances, it will n o t be necessary to
Perform ance T est a system as outlined below ; how ever, in
certain instances, the follow ing procedure may be advan­
tageous in diagnosing system m alfunction.
The follow ing fixed conditions m ust be adhered to in order
to make it possible to com pare the perform ance o f the system
being tested w ith the standards below:
1. D oors and w indow s closed. (Vehicle inside or in shade.)
2. H ood up and engine exhaust suitably ventilated.
3. Vehicle in N EU TR A L w ith engine running at 2000 rpm .
4. A ir C onditioning controls set fo r —
• M axim um cooling.
• High blow er speed.
N O T E : When running a Performance Test on a
C -62 and C-63 equipped vehicle, both systems
should be in operation.
the gauge lines from the
5. Gauge set installed.
6. System settled o u t (run-in approxim ately 10 m inutes).
7. A therm om eter placed in fro n t o f vehicle grille and
anoth er at the C-62 right fro n t upper outlet.
N O T E : Higher temperatures
occur at higher am bient temperatures. In areas of
high hum idity it is possible to have therm om eter
and gauge readings approach but not reach the
figures listed in the performance tables and still have
a satisfactorily operating unit. However, it is im por­
tant to remember that low pressure has a direct
relationship to nozzle o utlet tem perature. If pres­
sure is too low , ice w ill gradually form on the
evaporator fins, restricting airflow into the pas­
senger area and resulting in insufficient or no
cooling.

PERFORMANCE DATA

The follow ing Perform ance D ata define norm al operation
o f the system under the above conditions. Relative hum idity
does n ot appear in the tables because after running the
prescribed length o f tim e on recirculated air and m axim um
cooling, the relative h u m idity o f the air passing over the
evaporator core will rem ain at approxim ately 35% to 40%
regardless o f the am bient tem perature or hum idity.
S hould excessive head pressures be encountered at higher
am bient tem peratures, an 18" fan placed in fro n t o f the
vehicle and blow ing in to the condenser will provide the extra
circulation o f air needed to bring the pressures to w ithin the
lim its specified.
C-62 SYSTEM
Refrigerant Charge = 3 Lbs.—4 Ozs.
Tem perature o f
Air Entering the 7 0°
Condenser
Engine R.P.M.
Com pressor Head ISO-
Pressure* P.S.I.G . 145
Suction Pressure'1 ' 8-
P.S.I.G . 10
Discharge Air
T em p.* @ 41-
Upper right O utlet 44
C-62 & C-63 SYSTEM
Refrigerant Charge = 5 Lbs.—4 Ozs.
Tem perature o f
Air Entering
7 0 °
the Condenser
Engine R.P.M.
Com pressor Head
165-
Pressure* P.S.I.G . 180
S u ction Pressure*
12-
P.S.I.G .
15
Discharge Air
Tem p. *<® 40-
F ront C-62 O utlet
43
*When com pressor clu tch disengages
A IR C O N D IT IO N IN G 1A-19
and pressures will
80° 90° 100° 11 0 ° 1 20°
2 0 0 0
ISO- 160- ISO- 205- 240-
165 175 195 22 0 255
8- 8- 8- 11- 12-
10 10 10 14 15
41- 42- 50-
45- 55-
4 4
45 48 53 58
80° 9 0 ° 100° 110° 120°
2 0 0 0
175- 2 1 0 - 2 3 0 - 2 6 5 - 305-
190 225 245 2 8 0 320
14- 16- 20- 26- 31-
34
17 19 23 29
41- 52- 65-
45- 60-
4 4 48 68
55 63
C H E V Y V A N SH O P M A N U A L