Defender 90 NAS. Manual - part 89

AIR CONDITIONING

ADJUSTMENT

GENERAL PRECAUTIONS

The refrigerant used in the air conditioning system is
HFC (Hydrofluorocarbon) R134a.

WARNING: R134a is a hazardous liquid
and when handled incorrectly can cause
serious injury. Suitable protective clothing

must be worn when carrying out servicing
operations on the air conditioning system.

WARNING: R134a is odourless and
colourless. Do not handle or discharge in
an enclosed area, or in any area where the

vapour or liquid can come in contact with naked
flame or hot metal. R134a is not flammable, but
can form a highly toxic gas.

WARNING: Do not smoke or weld in areas
where R134a is in use. Inhalation of
concentrations of the vapour can cause

dizziness, disorientation. uncoordination,
narcosis, nausea or vomiting.

WARNING: Do not allow fluids other than
R134a or compressor lubricant to enter the
air conditioning system. Spontaneous

combustion may occur.

WARNING: R134a splashed on any part of
the body will cause immediate freezing of
that area. Also refrigerant cylinders and

replenishment trolleys when discharging will
freeze skin to them if contact is made.

WARNING: The refrigerant used in an air
conditioning system must be reclaimed in
accordance with the recommendations

given with a Refrigerant Recovery Recycling
Recharging Station.

NOTE: Suitable protective clothing
comprises: Wrap around safety glasses or
helmet, heatproof gloves, rubber apron or

waterproof overalls and rubber boots.

REMEDIAL ACTIONS

1. If liquid R134a strikes the eye, do not rub it.

Gently run large quantities of eyewash over the
eye to raise the temperature. If eyewash is not
available cool, clean water may be used. Cover
eye with clean pad and seek immediate medical
attention.

2. If liquid R134a is splashed on the skin run large

quantities of water over the area as soon as
possible to raise the temperature. Carry out the
same actions if skin comes into contact with
discharging cylinders. Wrap affected parts in
blankets or similar material and seek immediate
medical attention.

3. If suspected of being overcome by inhalation of

R134a vapour, seek fresh air. If unconscious,
remove to fresh air, apply artificial respiration
and/or oxygen and seek immediate medical
attention.

NOTE: Due to its low evaporating
temperature of -30

C, -22

F R134a should

be handled with care.

WARNING: Do not allow a refrigerant
container to be heated by a direct flame or
to be placed near any heating appliance. A

refrigerant container must not be heated above
50

C, 122

WARNING: Do not leave a container of
refrigerant without its cap fitted. Do not
transport a container of refrigerant that is

unrestrained, especially in the boot of a car.

AIR CONDITIONING

ADJUSTMENT

SERVICING PRECAUTIONS

Care must be taken when handling refrigeration
system components. Units must not be lifted by their
hoses, pipes or capillary lines. Hoses and lines must
not be subjected to any twist or stress. Ensure that
hoses are positioned in their correct run before fully
tightening the couplings, and ensure that all clips and
supports are used. Torque wrenches of the correct
type must be used when tightening refrigerant
connections to the stated value. An additional spanner
must be used to hold the union to prevent twisting of
the pipe.

Before connecting any hose or pipe ensure that
refrigerant oil is applied to the seat of the new ’0’ ring
but not to the threads.

Check the oil trap for the amount of oil lost.

All protective plugs on components must be left in
place until immediately prior to connection.

The receiver/drier contains desiccant which absorbs
moisture. It must be positively sealed at all times.

CAUTION: Whenever the refrigerant
system is opened, the receiver/drier must
be renewed immediately before evacuating

and recharging the system.

Use alcohol and a clean cloth to clean dirty
connections. Ensure that all new parts fitted are
marked for use with R134a.

Refrigerant oil

Use the approved refrigerant lubricating oil - Nippon
Denso ND-OIL 8.

CAUTION: Do not use any other type of
refrigerant oil.

Refrigerant oil easily absorbs water and must not be
stored for long periods. Do not pour unused oil back
into the container.

When renewing system components, add the
following quantities of refrigerant oil:

Condenser

40ml, 1.4 fl oz

............................................

Evaporator

80ml, 2.8 fl oz

............................................

Pipe or hose

20ml, 0.7 fl oz

..........................................

Receiver/drier

20ml, 0.7 fl oz

........................................

Total refrigerant oil in system = 180ml, 6.3 fl oz

A new compressor is sealed and pressurised with
Nitrogen gas. Slowly release the sealing cap, gas
pressure should be heard to release as the seal is
broken.

NOTE: A new compressor should always
have its sealing caps in place and these
must not be removed until immediately

prior to fitting

Fitting a new compressor

A new compressor is supplied with an oil fill (X) of
180ml, 5.3 fl oz.

A calculated quantity of oil must be drained from a
new compressor before fitting.

To calculate the quantity of oil to be drained:

1. Remove sealing plugs from the OLD

compressor.

2. Invert compressor and gravity drain oil into

measuring cylinder. Rotating the compressor
clutch plate will assist complete draining.

3. Note the quantity of oil drained (Y).
4. Calculate the quantity (Q) of oil to be drained

from the NEW compressor using the following
formula:

X - (Y + 20ml, 0.7 fl oz) = Q

Rapid refrigerant discharge

When the air conditioning system is involved in
accident damage and the circuit is punctured, the
refrigerant is discharged rapidly. The rapid discharge
of refrigerant will also result in the loss of most of the
oil from the system. The compressor must be
removed and all the remaining oil in the compressor
drained and refilled as follows:

1. Gravity drain all the oil, assist by rotating the

clutch plate (not the pulley).

2. Refill the compressor with 130ml, 4.6 fl oz of

new refrigerant oil.

3. Plug the inlet and outlet ports.

Servicing Equipment

The following equipment is required for full servicing
of the air conditioning system.

Recovery, recycling and charging station

- Leak detector
- Thermometer +20

C to -60

C, 70

F to -70

- Safety goggles and gloves

AIR CONDITIONING

ADJUSTMENT

REFRIGERANT RECOVERY, RECYCLING,
RECHARGING

Service repair no - 82.30.20/01

WARNING: The air conditioning system is
charged with a high pressure, potentially
toxic refrigerant. Repairs or servicing must

only be carried out by an operator familiar with
both the vehicle system and the charging and
testing equipment.

All operations must be carried out in a
well-ventilated area away from open flame and
heat sources.
Always wear safety goggles and gloves when
opening refrigerant connections.

WARNING: Wear eye and hand safety
protection. Open connections slowly in
case liquid or pressure is present. Allow to

bleed off slowly.

CAUTION: Overcharging air conditioning
system will cause excessive head
pressure.

An air conditioning portable Refrigerant Recovery
Recycling Recharging Station for use with R134a
refrigerant incorporates all the features necessary to
recover refrigerant R134a from the air conditioning
system, to filter and remove moisture, to evacuate and
recharge with the reclaimed refrigerant. The unit can
also be used for performance testing and air
conditioning system analysis.

The operator must adhere to the equipment
manufacturers’ instructions.

Recovery and recycling

1. Connect a Refrigerant Station to the high and

low pressure servicing connections.

2. Operate the refrigerant recovery system

according to the manufacturers instructions.

3. Measure the amount of oil discharged from the

system. Add an equal amount of new refrigerant
oil to compressor before evacuation sequence.

WARNING: Refrigerant must always be
recycled before reuse, to ensure that the
purity of the refrigerant is high enough for

safe use in the air conditioning system. Recycling
should always be carried out with equipment
which is design certified by Underwriter
Laboratory Inc. for compliance with SAE-J1991.
Other equipment may not recycle refrigerant to
the required level of purity.

A R134a Refrigerant Recovery Recycling
Recharging Station must not be used with any
other type of refrigerant.

Refrigerant R134a from domestic and commercial
sources must not be used in motor vehicle air
conditioning systems.

Evacuation and recharging

1. Add refrigerant oil to compressor if necessary.
2. Renew the receiver/drier.

CAUTION: When a major repair has been
carried out, a leak test should be carried
out using inert gas.

3. Connect a Refrigerant Station to the high and

low pressure servicing connections.

CAUTION: Whenever the refrigerant
system is opened, the receiver/drier must
be renewed immediately before evacuating

and recharging the system.

AIR CONDITIONING

ADJUSTMENT

4. Operate the refrigerant evacuation system

according to the manufactures instructions.

NOTE: If the vacuum reading is below 700
mm Hg, 28 in Hg after 15 minutes, suspect
a leak in the system. Partially recharge the

system and check for leaks using an electronic
leak tester. Check suction lines first, then run the
compressor for 5 minutes and then check the high
pressure lines.

CAUTION: The system must be Evacuated
immediately before recharging
commences. Delay between Evacuation

and Recharging is not permitted.

5. Operate the refrigerant recharging system

according to the manufacturer’s instructions.

Refrigerant to charge system = 900

30gm, 32

1 oz.

6. If the full charge has not been accepted by the

system, start the engine and run it at 1500
rev/min for a minimum of 2 minutes.
Switch on the air conditioning system, open the
vehicle windows, set the temperature control to
cold and switch the blower to maximum speed.

7. Consult Refrigerant Station Manual for correct

procedure to complete the charge.

8. Carry out the air conditioning system

performance test.

LEAK TEST SYSTEM

The following instructions refer to an electronic type
Refrigerant Leak Detector for use with R134a, which
is the safest and most sensitive.

CAUTION: When a major repair has been
carried out, a leak test should be carried
out using an inert gas (see below).

1. Place the vehicle in a well ventilated area but

free from draughts, as leakage from the system
could be dissipated without detection.

2. Follow the instructions issued by the

manufacturer of the particular leak detector
being used.

3. Commence searching for leaks by passing the

detector probe around all joints and components,
refrigerant gas is heavier than air.

4. Insert the probe into an air outlet of the

evaporator or into the evaporator drain tube.
Switch the air conditioning blower on and off at
intervals of ten seconds. Any leaking refrigerant
will be gathered in by the blower and detected.

5. Insert the probe between the magnetic clutch

and compressor to check the shaft seal for
leaks.

6. Check all service valve connections, valve plate,

head and base plate joints and back seal plate.

7. Check the condenser for leaks at the pipe

unions.

8. If any leaks are found, the system must be

discharged before rectification.

9. Rectify any leaks and recheck for leaks during

evacuation prior to charging.

Leak test using inert gas

Use Nitrogen or Helium gas.

1. Connect gas line to recharging station.
2. Pressurise system to 3 bar, 45 lbf/in

3. Carry out leak test as above.

Content .. 87 88 89 90 ..