Opel Frontera UE. Manual - part 20

1A–52

HEATING, VENTILATION AND AIR CONDITIONING (HVAC)

6. Perform a system leak test:

• Charge the system with approximately 200 g

(0.44 lbs) of HFC-134a.

• Make sure the high pressure valve of the manifold

gauge is closed.

• Check to ensure that the degree of pressure does

not change.

• Check for refrigerant leaks by using a HFC-134a

leak detector.

• If a leak occurs, recover the refrigerant. Repair

the leak and start all over again from the first step
of evacuation.

7. If no leaks are found, continue charging refrigerant

to the air conditioning system.

• Charge the refrigerant until the scale reading

decreases by the amount of the charge specified.

Specified amount: 650g (1.43lbs)

• If charging the system becomes difficult:

1 Run the engine at idle and close all the

vehicle doors.

2 Turn A/C switch “ON".

3 Set the fan switch to its highest position.

4 Set the air source selector lever to “CIRC".

5 Slowly open the low side valve on the

manifold gauge set.

WARNING:  Be absolutely sure not to open the high
pressure valve of the manifold gauge. Should the
high pressure valve be opened, the high pressure
refrigerant would flow backward, and this may
cause the refrigerant container to burst.

8. When finished with the refrigerant charging, close

the low pressure valve of the manifold gauge and
container valve.

9. Check for refrigerant leaks.

Checking The A/C System

1. Run the engine and close all the vehicle doors.

2. Turn A/C switch “ON", set the fan switch to its

highest position.

3. Set the air source lever to “CIRC", set the

temperature lever to the full cool position.

4. Check the high and low pressure of the manifold

gauge.

• Immediately after charging refrigerant, both high

and low pressures might be slightly high, but they
settle down to the pressure guidelines shown
below:

• The ambient temperature should be between 25–

30

°

C (77–86

°

F).       

• The pressure guideline for the high-pressure side

is approximately 1372.9–1863.3 kPa (199.1–
270.2 psi).

• The pressure guideline for the low-pressure side

is approximately 147.1–294.2kPa (21.3–42.7
psi).

• If an abnormal pressure is found, refer to

Checking The Refrigerant System With Manifold
Gauge in this section.

5. Put your hand in front of the air outlet and move the

temperature control lever of the control panel to
different positions.  Check if the outlet temperature
changes as selected by the control knob.

Reading Sight Glass

The sight glass provides accurate diagnosis only under
the following conditions.
If the vehicle can be tested under these conditions,
check the sight glass appearance and compare to the
chart below.

• Engine speed idle

• A/C switch “ON"

• Blower fan operating at highest speed

• Air source selector lever at “RECIRC"

• Temperature control lever at coldest position

• Ambient temperature below 30

°

C (86

°

F) and

humidity below 70% (See NOTE 1)

• High side pressure less than 1667.1 kPa (241.7 psi)

(See NOTE 2)

NOTE:  1. If the vehicle cannot be moved to a testing
location that meets these specifications, then the sight
glass cannot be used for diagnosis. You must discharge
and recover the refrigerant, then recharge the system
with the specified amount of refrigerant.
Then continue checking the system performance.

NOTE:  2. If the high side pressure is greater than
stated, the sight glass cannot be used for diagnosis. You
must discharge and recover the refrigerant, then
recharge the system with the specified amount of
refrigerant. Then continue checking system
performance.

HEATING, VENTILATION AND AIR CONDITIONING (HVAC)

1A–53

High and low 
pressure pipe 
temperature

The high pressure
pipe is hot and the
low pressure pipe is
cold. There is a
distinct difference in
temperature between
them.

The high pressure
pipe is warm and the
low pressure pipe is
cool. There is no
great difference in
temperature between
them.

There is litttle
difference in
temperature between
the high pressure
pipe and the low
pressure pipe.

The high pressure
pipe is hot and the
low pressure pipe is
slightly warm. There
is a defference in
temperature between
them.

Slight glass condition

Almost transparent. A 

flow of bubbles can 

be seen, but they 

disappear when the 

throttle is opened.

A flow of bubbles 

always can be seen. 

It appears sometimes 

transparent, and 

sometimes frothy.

Something like fog 

faintly can be seen.

Even at idle with the 

fan at “HI” (with the 
window fully open), 

the bubbles cannnot 

be seen.

Air conditioning cycle 
condition

OK

NG

(Not enough 

refrigerant)

NG

(Almost no 

refrigerant)

NG

(Too much 

refrigerant)

1A–54

HEATING, VENTILATION AND AIR CONDITIONING (HVAC)

Compressor Assembly

Compressor Assembly and Associated Parts (6VD1)

871RX021

EndOFCallout

Removal

1. Disconnect the battery ground cable.

2. Discharge and recover refrigerant

• Refer to Refrigerant Recovery in this section.

3. Disconnect magnetic clutch harness connector.

4. Remove serpentine belt.

• Move serpentine belt tensioner to loose side

using wrench then remove serpentine belt.

Legend

(1) Magnetic Clutch Harness Connector
(2) Refrigerant Line Connector

(3) Compressor
(4) Serpentine Belt

HEATING, VENTILATION AND AIR CONDITIONING (HVAC)

1A–55

850RX003

EndOFCallout

5. Disconnect refrigerant line connector.

• When removing the line connector, the

connecting part should immediately be plugged
or capped to prevent foreign matter from being
mixed into the line.       

6. Remove compressor.

Installation

1. Install compressor.

• Tighten the compressor fixing bolts to the

specified torque.

Torque: 19N•m (14 lb•ft)

2. Connect refrigerant line connector.

• Tighten the refrigerant line connector fixing bolts

to the specified torque.

Torque: 15N•m (11 lb•ft)

• O-rings cannot be reused. Always replace with

new ones.

• Be sure to apply new compressor oil to the

O-rings when connecting refrigerant lines.

3. Install serpentine belt.

• Move serpentine belt tensioner to loose side

using wrench, then install serpentine belt to
normal position.

4. Connect magnetic clutch harness connector.

Legend

(1) Tensioner
(2) Idler Pulley
(3) Cooling Fan Pulley
(4) Serpentine Belt
(5) Power Steering Oil Pump
(6) Air Conditioner Compressor
(7) Crankshaft Pulley
(8) Generator