1973 OPEL 1900 Service Manual

AIR CONDITIONER SYSTEM. OPEL 1900. MANTA9B- 93
2. Remove the left side of distributor duct, and the
in-line fuse. See Figure 9B-174.98.139Figure SB-174 Location of Distributor Duct (Left Side)
Retaining Screws
Figure SB-175 Removing Left Side Distributor Duct
3. Rembve the glove box assembly. See Figure 9B-
176.
4. Discharge refrigerant from system, (refer to DIS-
CHARGING SYSTEM) and disconnect refrigerant
hose from evaporator outlet and pipe from evapora-
tor inlet’and tape the open ends of the refrigerant
lines and evaporator pipes. See Figure
9B-178.5. Disconnect the delay restrictor and check valve
hose assembly from the vacuum cut-off switch and
disconnect the electrical wiring. See Figure
9B-180.6. Rempve evaporator inlet and outlet pipes re-
tainer and rubber grommet. See Figure
9B-178.Figure SB-176 Glove
Bdx Removed
Figure SB-178 Location of Refrigerant Hoses, Pipes,
Vacuum Cut Off Switch and Evaporator Attaching Bolt
(Left Side)
Figure 9B-180 Vacuum Hoses and Wiring

98.94 1973 OPEL SERVICE MANUAL
7. Remove 2 upper evaporator attaching nuts. See
Figures 9B-178 and 9B-181.
Figure 98-181 Location of Upper Evaporator
Attaching Bolt (Right Side)
8. Remove 2 attaching case mpunting bracket to
instrument panel screws. See Figure 9B-182.
Figure SB-182 Evaporator and Blower AssemblyBrackets and Attachments9. From underneath evaporator case, disconnect
two (2) drain hoses.lo. Carefully
PXIIOVS assembly from car. See Figure
9B-184.
11. Disconnect resistor electrical connector and
remove resistor assembly. See Figure
9B-184.12. Remove the blower case and blower motor at-
taching screws and remove assembly. See Figure 9B-
184.Installation
1. Install the blower motor assembly into caseFigure 98-183 Drain Hose
BLOWER MOTOR
Figcre 98.184 Assembly Removed
bracket with the electrical connector side of the mo-
tor to the right side ofthe bracket. Attach the mount-
ing strap.
2. Assemble the case halves and attach the cover
plate.
3. Install the resistor assembly and electrical con-
nector. Install blower motor connector. See Figure
9B-184.4. Install assembly into car carefully guiding
evaporator pipes up through cowl opening. See Fig-
ure 9B-185.
5. Install 2 upper evaporator attaching nuts. See
Figures 9B-178 and 9B-181.
6. Install 2 attaching case mounting bracket to in-
strument panel screws. See Figure 9B-182.

AIR CONDITIONER SYSTEM -OPEL 1900 - MANTA9B- 95
Figure 96.185 Evaporator Inlet and Outlet Pipes andO-Rings
7. Connect the 2 drain hoses underneath evapora-
tor.
8. Install evaporator inlet and outlet pipes retainer
and rubber grommet. See Figure
9B-178.
9. Connect vacuum cut-off switch and electrical
wiring,, making sure the delay restrictor and check
valve hose are installed correctly. See Figure
9B-180.
10. Install refrigerant hoses and pipes using new o-
rings on line fittings and evacuate system. Refer to
EVACUATING SYSTEM.
Il. While system is being evacuated install the in-line
fuse and left side of distributor duct. See Figure
9B-
174.
12. Install the glove box.
Figure 98.186 Delay Restrictor and Check Valve Hose
Assembly
Figure 9B-187 Fuse Block Connections
13. Install negative battery cable and charge the sys-
tem. Refer to CHARGING SYSTEM.

98.96 1973 OPEL SERVICE MANUALr DARK BLUE
LIGHT BLUE STRIPE
CUTOUT111111DARK GREEN DARK GREEN
,,
I
,\,\
BATTERYl LJ
\flu- +tL-2+- -7- -RESISTOR
A
EXlSilNG‘IWIRE
I
I
IFUSE BLOCK*,*,- I./SWITCH
r
ti‘WIREfIfI
1- IAAI
i$+.-lAC~,‘XESW WIRE
I I
TTEVAPO.RATOREVAPO.RATOR
BLACK WITH RED STRIPE BLACK WITH RED
Sl96-143
Figure 9B-188 Wiring Schematic‘RIPE96-143
Figure 9B-188 Wiring Schematic
SPECIFICATIONS
Blower Motor Type
......................................................................................................12 VDC
Blower Fan Type
..................................................................................................Squirrel Cage

AIR CONDITIONER SYSTEM - GT96. 97
AIR CONDITIONER SYSTEM
GTCONTENTS
Subject
: DESCRIPTION AND OPERATION:
General Description of System
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Operation of Controls
. . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .DIAGNOSIS:
Diagnosis Guide
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .MAINTENANCE AND ADJUSTMENTS:
Adjustment of Thermostatic Switch
. . . . . . . . . . . . . . . . . . . . . . .MAJOR REPAIR:
Removal 8 Installation of Vacuum Switch.
Removal&InstallationBlowerSwitch. . . . . . . . . . . . . . . . . . . . . .Removal & Installation Temperature Control Switch
. . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . .
Removal&InstallationResistor Assembly. . . . . . . . . . . . . .Removal & Installation Blower Motor Assembly . .
SPECIFICATIONS:
Specifications
. . .
. . . . . . . . * . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Page No.
9BL 97
9Bi 97
9BL 98
98: 98
9B: 99
9B; 99
9B- 99
98~10098-101
9B-104
DESCRIPTION AND OPERATIONAir Knob
GENERAL DESCRIPTION OF SYSTEMTurning the AIR knob clockwise operates the three-
speed blower motor.
The air &mditioner is intended to give maximum
cooling comfort within the vehicle. To do this, care-
ful attention must be given to the following sections.
The system operates on recirculated air only and is
entirely @dependent of the vehicle heater.Temp Knob
Recirculated inside air is drawn into the unit, passed
through the evaporator core and into the car through
the adjustable outlets in the duct assembly.This knob may be regulated to cohtrol the degree of
cooling desired. Fully clock-wise provides maximum
cooling; however, turning the kndb to the center de-
tent position provides adequate cooling for highway
operation.
CONTROLSWhen maximum cooling is reqlired, outside air
should not be admitted to the car.
System c&trols are the AIR knob controlling the
three
spe&d blower motor switch and the TEMPWhen the unit is set for maximum cooling and the
vehicle is being driven continuously at highway
knob which controls the setting of the thermostaticspeeds or at elevations of 4,000 ft. or more, there is
switch. When operating this system, the heater musta possibility of the formation of ice on the evaporator
be off for maximum cooling.core tins.

98.98 1973 OPEL SERVICE MANUALDIAGNOSISTROUBLE DIAGNOSIS GUIDE
Insufficient Cooling
CHECK AIR FLOW
FAN DOES NOT RUN
- Correct electrical fault.
FAN RUNS
- Check air velocity.
NOT OK
- Clean evaporator inlets.
Clean evaporator core.
Clean evaporator outlets.
OK
- Check refrigeration (refer to Refrigeration
Diagnosis Guide).
MAINTENANCE AND ADJUSTMENTS
ADJUSTMENT OF THERMOSTATIC SWITCHThe system makes use of a thermostatic switch with
a self-supporting air sensing capillary. This capillary
controls the switch by sensing the temperature of the
air leaving the evaporator tins.
Checking for Proper Operation
1. Install the gauge set, and set up the vehicle as
described under FUNCTIONAL TESTING SYS-
TEM in Refrigerant Components Section.
2. Movement of the temperature control knob
should result in a definite change in suction pressure
and cycling of the compressor clutch.
3. If compressor continues to operate regardless of
the knob adjustment it indicates that the switch
points are fused, which will lead to evaporator
freeze-up. The switch should be replaced.
Adjusting Switch
If after the foregoing checks, the switch seems to be
operating correctly, adjust for proper setting if neces-
sary, as follows:
1. Set up car as described in FUNCTIONAL
TESTING SYSTEM in Refrigerant Components
Section.
2. The suction side of the system, read on the lowpressure gauge, should pull down to the pressure
shown in the chart in SPECIFICATIONS in Refrig-
erant Components Section.
3. Remove the duct assembly mtaining screws and
remove the duct assembly noting the position of the
air sensing capillary so that it can be reinstalled in
the same location as when removed. See Figure 9B-
190.Figure 98.190 Duct Assembly and Retaining Screws
Figure 9B-13 1 Duct Assembly
4. Remove the thermostatic switch retaining screws
and remove switch. Remove the non-metal end plate
from the switch to gain access to the switch adjusting
screw. Check the screw for stripped or otherwise
damaged threads.

5. If the low side pressure was less than the pre-
scribed pressure at the end of each cooling cycle, turnthe adjusting screw a partial turn clockwise. See Fig-ure 9B-192.AIR CONDITIONER SYSTEM
- GT9B- 99
CONNECTOR
Figure 98.192 Adjusting Thermostatic Switch6. If the pressure was more than the prescribed
value, tuin the adjusting screw counter-clockwise.7. Reinstall switch end plate and install switch in
face plate. Install face plate on evaporator assembly
assuring
,that the air sensing capillary has been re-
placed properly.
Figure 98-l 93 Vacuum Switch8. Check system performance. Iffurther adjustment
is needed, repeat steps 3 thru 7 until the correct
pressure is reached.
REMOVAL AND INSTALLATION OF BLOWER
SWITCHDo not attempt to run a performance test with the
duct assembly and switch removed from the
evaporator assembly
- inaccurate readings will re-
sult. Always replace the switch and duct assemblies
before c+ecking the system performance.
Removal
MAJOFi REPAIR
1. Remove the negative cable from the battery2. Remove the retaining screws from the duct as-
sembly. See Figure
9B-190.3. Remove 2 blower switch rejaining screws and
remove blower switch.
REMOVAL AND INSTALLATION OF VACUUM
SWITCH,
Installation
Ramoval~1. Remove right trim pad below instrument panel.
2. Rembve two (2) screws and unplug the vacuum
hose and electrical connector. See Figure
9B-193.1. Install the blower switch and
secure with two (2)
retaining screws.
2. Install the duct assembly retaining screws.
3. Install the negative battery cable.
Installation1. Install two (2) screws and plug in electrical con-
nector and connect the delay restrictor and checkvalve
hose assembly.
I
REMOVAL AND INSTALLATIDN:OF
TEMPERATURE CONTROL SWITCH
Removal2. Install right trim pad.I. Remove the negative battery cable.

gB-100 1973 OPEL SERVICE MANUAL
2. Remove the retaining screws from the duct as-
sembly. See Figure 9B-190.3. Lift up duct assembly and note the position of the
air sensing capillary so that it can be reinstalled in
the same location as when removed.
4. Remove the temperature control switch retaining
screws and remove switch.
Installation
1. Install the temperature control switch and secure
with the retainer screws.
2. Position the air sensing capillary in the exact
location as was noted when removing.
3. Install the duct assembly retaining screws.
4. Install the negative battery cable.
REMOVAL AND INSTALLATION OF RESISTOR
ASSEMBLY
Removal1. Remove the negative battery cable from the bat-
tery.2. Remove the luggage tray attaching screws and
lift out tray. See Figure 9B-194.
Figure 98-194 Luggage Tray3. Remove all evaporator cover attaching screws
and remove cover. See Figure
9B’-195.Figure 98.195 Evaporator Cover Assembly and
Attaching Screws
4. Remove the electrical plug connector from the
resistor assembly.
5. Remove 2 resistor attaching screws and remove
resistor assembly. See Figure 9B-197.
/98-147Figure 9B-196 Resistor and Blower Motor
Connections