Caution--Liquid Indicator; Depressurizing The System-All; Evacuating The System; Preparati~Ns For Evacuating Complete System - Pontiac Grand Prix Service Manual

1A-2 1969 PONTIAC SERVICE MANUAL
3. Sealing caps should be removed from sub-assem-
blies just prior to making connections for final
assembly.
4. Use a small amount of clean refrigeration oil (525 or
1000 visosity) on all tube and hose joints, and dip the
O-ring gasket in this oil before assembling joint, as
this oil will help in making a leak-proof-joint.
.
When tightening joints, use another wrench to hold
stationary part of the connection, so that a solid feel
can be attained, which will indicate proper assembly.
CAUTION: Tighten all tubing connections as shown in
Fig. 1A-1. Insuficient or excessive torque when tightening
can result in loose joints or deformed joint parts, either
condition can result in refrigeration leakage.
5. Do not connect receiver dehydrator indicator assembly
until al'l other sealed sub-assemblies have been connected.
This is necessary to insure optimum dehydration and
maximum moisture protection of the refrigeration system.
CAUTION--LIQUID INDICATOR
PONTIAC. G R A N D PRlX AND TEMPEST
Under normal conditions, receiver-dehydrator will
show clear with about 3-1/2 pounds of refrigerant in
the system. However, the air conditioner will not
produce its best performance until 4-1/8 pounds of
refrigerant are in the system. Do not overcharge with
refrigerant, as this will result in extremely high head
pressures and the compressor safety valve will blow.
FIREBIRD
Under normal conditions, liquid indicator will show
clear with about 2-3/4 pounds of refrigerant in the
system. However, the air conditioner will not produce
its best performance until 3-3/4 pounds of refrigerant
are in the system. Do not overcharge with refrigerant,
as this will result in extremely high head pressures and
the compressor safety valve will blow.
If o connection is mode with steel to aluminum or
cop-r, use torques for aluminum. In other words,
Fig. 1A-1 Pipe and Hose Connection Torque Chart
DEPRESSURIZING THE SYSTEM-ALL
1.
Remove caps from suction gauge fitting on P.O.A.
valve and discharge valve gauge fitting on compressor.
2. With both valves on manifold gauge set J 5725-01
closed (clockwise), attach manifold to P.O.A. valve and
compressor, using J 5420 Schrader valve adapter at
suction gauge fitting and J 6163 Schrader valve
adapter at discharge gauge fitting.
3. Crack open high pressure valve on manifold gauge
set to allow slow escape of refrigerant from system
through the manifold gauge set and out center fitting
and hose. (Place end of hose in clean container.). If oil
drips from hose into the container, refrigerant is
escaping too rapidly.
4. When hissing ceases (indicating all refrigerant has
.
escaped) close high pressure valve on manifold gauge
set by turning valve clockwise.
EVACUATING THE SYSTEM
When refrigeration system is &pressurized and
opened for service, some air will enter lines regardless
of how quickly openings are capped. In order to
remove this air and as much as possible of the
moisture it contains, the complete system must be
evacuated. Evacuating is merely the process of remov-
ing all air from the system, thereby creating a vacuum
in the system.
CAUTION: Under no circumstances should alcohol be
used in the system in an attempt to remove moisture,
regardless of the successful use of alcohol in other refrig-
eration systems.
PREPARATI~NS FOR EVACUATING COMPLETE
SYSTEM
1.
Check the low pressure gauge for proper calibration,
with the gauge disconnected from the refrigeration
system. Be sure that the pointer on the guage indicates
to the center of 0. Tap gauge a few times lightly to be
sure pointer is not sticking. If necessary, calibrate as
follows:
a. Remove cover from gauge.
b. Holding gauge pointer adjusting screw firmly with'
one hand, .carefully force pointer in the proper
direction in proper amount to position pointer through
the center of 0 position. Tap gauge a few times to be
sure pointer on gauge is not sticking. Replace gauge
cover.
2. If gauge set is not already connected to P.O.A. valve
and compressor, connect as follows (Fig. 1A-2).