1988 PONTIAC FIERO Service Repair Manual

1B-6 AIR CONDlTlONlNC
"OFF" POSITION WITH OUTSIDE AIR DISTRIBUTED ABOUT 80%
2-IN THIS MODE LEVER POSITION, MAXIMUM TO
FLOOR (AND 20% TO WINDSHIELD AND
COOLING IF OFFERED WITH THE CONDITIONED SIDE WINDOWS -SOME MODELS)
AIR DISTRIBUTED THROUGH I.P. OUTLET AND 7-CONDITIONED
AIR DISTRIBUTED ABOUT 80% SLIGHT AMOUNT TO FLOOR AT ANY BLOWER TO
WINDSHIELD AND SIDE WINDOWS, AND
20% TO FLOOR
3-CONDITIONED AIR IS DIRECTED THROUGH
I.P. 8-TEMPERATURE LEVER POSITION REGULATES
AND FLOOR DISTRIBUTOR OUTLETS WITH TEMPERATURE OF THE AIR ENTERING THE
SOME ALSO TO WINDSHIELD PASSENGER
COMPARTMENT BY CABLE
4-CONDITIONED AIR IS DIRECTED THROUGH
I.P. OPERATION OF THE HEATER CORE
AND FLOOR DISTRIBUTOR OUTLETS WITH TEMPERATURE DOOR
SOME ALSO TO WINDSHIELD 9-VACUUM
OPERATED SYSTEM SELECTOR (MODE)
5-A NON-COMPRESSOR OPERATING POSITION, LEVER
WITH OUTSIDE AIR DELIVERED THROUGH 10-FAN CONTROL
(DESIGN VARIES WITH MODEL) I.P. OUTLETS
Figure 4 AIC Controller -- Typical
Figure 5 A/C Functional Testing

AIR GONDlTlONlNG 1B-7
REFRIGERANT - 12
PRESSURE - TEMPERATURE
RELATIONSHIP
The table below indicates the pressure of Refri-
gerant - 12 at various temperatures. For in-
stance, a drum of Refrigerant at a temperature
of
&!OF (26.%C) will have a pressure of 84.1 PSI
(579.9 kPa). If it is heated to 129 F (51.%C), the
pressure will increase to 167.5 PSI (1154.9
kPa). It also can be used conversely to deter-
mine the temperature at which Refrigerant - 12 boils under various pressures. For example,
at a pressure of 30.1 PSI (207.5 kPa), Refriger-
ant - 12 boils at 32F ((PC).
O(ATM0SPHERIC PRESSURE)
2.4
4.5
Figure 7 A/C System Performance Test

1B-8 AIR CONDITIONING
INSUFFICIENT COQblNG "CHART A
A/C FUSE AND/OR GAGE FUSE.
OR DISCONNECTED
AlC WIRE CONNECTOR.
. CHECK BLOWER FOR FAN OPERATION.
. ENGINE COOLING FAN OPERATION (FAN OPERATES IN ALL A/C MODES AS FOLLOWS:
A. DISCONNECT ENGINE COOLANT TEMPERATURE FAN SWITCH.
8. WITH IGNITION ON AND ENGINE NOT RUNNING, SET A/C CONTROL TO A/C MODE.
C. ENGINE COOLING FAN SHOULD RUN.
D. RECONNECT ENGINE COOLANT TEMPERATURE FAN SWITCH.
REPLACE COMPRES-
SOR ASSEMBLY. RE-
PLACE ORIFICE. EVA-
CUATE AND CHARGE. AS
REQUIRED
AND 'HIGH' BLOWER.
T
AUXIL I ARY FAN IN T OF VEHICLE.
I OFF ALL THE TIME I
RESTRICTION IN HIGH
SIDE OF SYSTEM.
VISUALLY CHECK FOR
FROST SPOT TO LOCATE
RESTRICTION. REPAIR.
Figure
8 C.C.O.T. NC System Insufficient Cooling Diagnostic Procedure (1 of 4)

AIR CONBiTlQNlMG 1B-9
C.6.O.T SYSTEM AIR CO~dDITlON1NG DIAGNOSIS
INSUFFICIENT COOLING "CHART
B"
COMPRESSOR ASSEMBLY.
PRESSURE AT THE ACCUMULATOR.
C.C.O.T. SYSTEM AIR CONDITIONING DIAGNOSIS
INSUFFICIENT COOLING "CHART C"
ADD .45 kg (ONE LB) OF REFRIGERANT-12
AND THEN CHECK CLUTCH CYCLE RATE.
THAN INLET
Figure 9 C.C.O.T. AIC System Insufficient Cooling Diagnostic Procedure (2 of 4)

1 B-10 AIR COMDIP"18NING
G.C.O.T. SYSTEM AIR CONDITIONING DIAGNOSIS
INSUFFICIENT COOLING
" CHART D"
PERFORMANCE CHART FOR C.G.O.T. SYSTEMS
CONDENSER
COMPRESSOR OUT PSI
(KPA) (950-1 200)
ACCUMULATOR (KPA) (1 50-1
93)
AVERAGE A/C
AIR DISCHARGE

AIR CONBlTiONlNG 1 B-1 1
CHARGE SYSTEM AND CHECK FOR
Figure 11 C.C.Q.T. NC System Insufficient Cooling Diagnostic Procedure (4 of 4) i I

18-12 AIR CONDITIONING
ELEGTRICAWACUUM SYSTEM
DIAGNOSIS
When diagnosing problems in the electrical sys-
tems of the air conditioning system, consult section
8A.
LEAK TESTING THE REFRIGERANT
SYSTEM
Whenever a refrigerant leak is suspected in the
system or a service operation performed which results
in disturbing lines or connections, it is advisable to
test for leaks.
Liquid Leak Detectors
There are a number of locations (fittings,
valves, etc.) on the air conditioning system where a
liquid leak detector solution may be used to pinpoint
refrigerant leaks.
By applying test solution to the area in question
with the swab that is attached to the bottle cap, bub-
bles will form within seconds if there is a leak.
For restricted access areas, such as sections of
the evaporator and condenser, an electronic leak
detector, such as
5-29547 or equivalent, is more prac-
tical for determining and locating leaks.
3-LOW BATTERY
INDICATOR
2-HI-LOW SWITCH
4-BALANCE CONTROL
Figure 12 Electronic Leak Detector J-29547
ELECTRONIC LEAK TESTERS
(Figure 12)
Electronic leak testers can accurately determine
leaks in areas that are difficult to test with liquid leak
detectors due to poor visibility or inaccessibility.
The H-10 Leak Detector 5-26934 is a 110-volt,
A/C powered tester while the Refrigerant Leak Detec-
tor J-29547 is a portable, battery operated model.
Both models provide visual
and/or audible signals to
indicate leak detection.
The successful use of electronic leak detectors
depends upon carefully following the manufacturer's
instructions regarding calibration, operation and
maintenance. Battery condition is especially impor-
tant to the accuracy of the portable battery powered
model
5-29547 and is monitored by a low battery
indicator.
SERVICE PROCEDURES
Before attempting any service which requires
opening of refrigerant lines or components, the person
doing the work should be thoroughly familiar with the
information under HANDLING REFRIGERANT- 12,
HANDLING REFRIGERANT LINES AND FIT-
TINGS AND MAINTAINING CHEMICAL STA-
BILITY IN THE REFRIGERATION SYSTEM. Very
carefully follow the DISCHARGING, ADDING OIL,
EVACUATING AND CHARGING PROCEDURES
FOR
A/C SYSTEMS instructions given on the fol-
lowing pages for the unit being serviced.
Sealing caps should be removed from sub-
assemblies just prior to making connections for final
assembly. Use a small amount of clean 525 viscosity
refrigerant oil on all tube and hose joints. Always use
new O-rings dipped in the clean 525 viscosity refrig-
erant oil when assembling joints. The oil will aid in
assembly and help provide a leak-proof joint. When
tightening joints, use a second wrench to hold station-
ary part of connection so that
a solid feel can be
attained. This will indicate proper assembly.
Tighten all tubing connections as shown in
torque chart (Figure
13). Insufficient or excessive
torque when tightening can result in loose joints or
deformed joint parts. Either condition can result in
refrigerant leakage.
O-RING REPWCEMENT
Install new G. M. approved service replacement
air conditioning
"0" rings whenever a joint or fitting
is disassembled, except when provided on new com-
ponents. Even though an
"0" ring may look the same,
it is extremely important that only recommended ser-
vice replacement air conditioning
"0" rings be used or
excessive leakage of Refrigerant 12 may occur.

-
AIR CONDlTlQNlNG 1B-'13
METAL TUBE
THREAD AND
FITTING SIZE
Figure 13 Pipe 8( Hose
CAPTURED NOM-CAPTURED
Figure 14 0-Ring Designs
When replacing "0" rings on an air conditioning
components or joint connections, the fitting design
should be carefully identified to ensure installation of
correct air conditioining service replacement
"0"
rings. Some joint connections and components will
implement a "captured"
"0" ring design fitting that
uses a groove to retain the
"0" ring, while others do
not have a groove and uses a "non-captured" or "stan-
dard"
"0" ring.
Assembly and tightening procedures are the
same for both designs, however, the
"0" rings are
different. Some
"0" rings are color coated to ease
indentification and assembly. The following is a list
showing the color applications for the currently ser-
viced air conditioning
"0" rings:
A. Red
- Captured
(Grooved Male Fitting End
Fom) "0 " Ring Design.
B . Blue - Non-captured/Standard (Straight Male
Fitting End
Form) "09' Ring Design.
61. Yellow - "0" rings used on different types of
air conditioning switches.
These colored "O" rings are available in various
sizes for each application.
"0" rings should be coated
with
525 viscosity refrigerant oil, prior to installation,
but must not be soaked. Soaking color coated
"0"
rings will cause them to swell.
Connection Torque Chart
NOTICE: Do not soak the new teflon coated
"0" ring seals in refrigerant oil, it can cause
refrigerant leakage due to improper joint assem-
bly. Prolonged exposure, such as soaking, may
swell them large enough to prohibit joint assem-
bly.
ALWAYS SLIP THE 6"O" RING ONTO
THE FLANGE TUBE TO ENSURE PROPER
LOCATION AND SEALING.
Also, prior to installation, verify that both "09'
rings and fittings have not been nicked or deformed.
Deformed or nicked
parts must be replaced. Failure to
use the proper service replacement parts and proce- dures may result in excessive Refrigerant
12 leakage.
HANDLING REFRIGERANT12
Air conditioning systems contain Refrigerant-
12. This is a chemical mixture which requires special
handling procedures to avoid personal injury.
Always wear goggles and wrap a clean cloth
around fittings, valves, and connections when per-
forming work that involves opening the refrigerant
system.
Always work in a well ventilated area and
avoid breathing
any refrigerant fumes. Do not weld
or steam clean on or near any car-installed air condi-
tioning lines or components.
If Refrigerant-12 should come in contact with
any part of the body, flush the exposed area with
water.
All
Refrigerant-12 drums are shipped with a
heavy metal screw cap. The purpose of the cap is to
protect the valve and safety plug from damage. It is
good practice to replace the cap after each use of the
drum.
If it is necessary to transport or carny any con-
tainer of Refrigerant-12 in a vehicle, do not
carry it in
the passenger compartment. If the occasion arises to
fill a
sfnall Refrigerant-12 drum from a large one,
never fill the drum completely. Space should always
be allowed above the liquid for expansion.