air conditioning LAND ROVER DISCOVERY 1995 Repair Manual

82AIR CONDITIONING
6
ADJUSTMENT SYSTEM TEST
1.Place the vehicle in a ventilated, shaded area
free from excessive draught, with the doors and
windows open.
2.Check that the surface of the condenser is not
restricted with dirt, leaves, flies, etc. Do not
neglect to check the surface between the
condenser and the radiator. Clean as necessary.
3.Switch on the ignition and the air conditioner air
flow control. Check that the blower is operating
efficiently at low, medium and high speeds.
Switch off the blower and the ignition.
4.Check that the evaporator condensate drain
tubes are open and clear.
5.Check the tension of the compressor driving belt,
and adjust if necessary.
6.Inspect all connections for the presence of
refrigerant oil. If oil is evident, check for leaks,
and repair as necessary.
NOTE: The compressor oil is soluble in
Refrigerant R134a and is deposited when
the refrigerant evaporates from a leak.
7.Start the engine.
8.Set the temperature controls to cold and switch
the air conditioner blower control on and off
several times, checking that the magnetic clutch
on the compressor engages and releases each
time.9.With the temperature control at maximum
cooling and the blower control at high speed,
warm up the engine and fast idle at 1000
rev/min. Check the sight glass for bubbles or
foam. The sight glass should be generally clear
after five minutes running, occasional bubbles
being acceptable. Continuous bubbles may
appear in a serviceable system on a cool day, or
if there is insufficient air flow over the condenser
at a high ambient temperature.
10.Repeat at 1800 rev/min.
11.Gradually increase the engine speed to the high
range, and check the sight glass at intervals.
12.Check for frosting on the service valves.
13.Check the high pressure hoses and connections
by hand for varying temperature. Low
temperature indicates a restriction or blockage at
that point.
14.Switch off the air conditioning blower and stop
the engine.
15.If the air conditioning equipment is still not
satisfactory, carry out a pressure test as
previously described in this section.
COMPRESSOR DRIVE BELT
Service repair no - 82.10.01.
Tdi -
See ENGINE, Repair, Compressor drive belt
V8i and MpiSee ENGINE, Repair, Drive belt

AIR CONDITIONING
1
REPAIR PRECAUTIONS IN HANDLING REFRIGERANT
LINES
WARNING: Wear eye and hand protection
when disconnecting components
containing refrigerant. Plug all exposed
connections immediately.
1.When disconnecting any hose or pipe
connection the system must be discharged of all
pressure. Proceed cautiously, regardless of
gauge readings. Open connections slowly,
keeping hands and face well clear, so that no
injury occurs if there is liquid in the line. If
pressure is noticed, allow it to bleed off slowly.
2.Lines, flexible end connections and components
must be capped immediately they are opened to
prevent the entrance of moisture and dirt.
3.Any dirt or grease on fittings must be wiped off
with a clean alcohol dampened cloth. Do not use
chlorinated solvents such as trichloroethylene. If
dirt, grease or moisture cannot be removed from
inside the hoses, they must be replaced with
new hoses.
4.All replacement components and flexible end
connections must be sealed, and only opened
immediately prior to making the connection.
5.Ensure the components are at room temperature
before uncapping, to prevent condensation of
moisture from the air that enters.
6.Components must not remain uncapped for
longer than fifteen minutes. In the event of delay,
the caps must be fitted.
7.Receiver/driers must never be left uncapped as
they contain Silica Gel crystals which will absorb
moisture from the atmosphere. A receiver/ drier
left uncapped must not be used, fit a new unit.
8.The compressor shaft must not be rotated until
the system is entirely assembled and contains a
charge of refrigerant.
9.A new compressor contains an initial charge of
of refrigerant oil. The compressor also contains a
holding charge of gas when received which
should be retained by leaving the seals in place
until the pipes are re-connected.10.The receiver/drier should be the last component
connected to the system to ensure optimum
dehydration and maximum moisture protection of
the system.
11.All precautions must be taken to prevent
damage to fittings and connections. Slight
damage could cause a leak with the high
pressures used in the system.
12.Always use two wrenches of the correct size,
one on each fitting when releasing and
tightening refrigeration unions.
13.Joints and 'O' rings should be coated with
refrigeration oil to aid correct seating. Fittings
which are not lubricated with refrigerant oil are
almost certain to leak.
14.All lines must be free of kinks. The efficiency of
the system is reduced by a single kink or
restriction.
15.Flexible hoses should not be bent to a radius
less than 90mm.
16.Flexible hoses should not be within 100mm of
the exhaust manifold.
17.Completed assemblies must be checked for
refrigeration lines touching metal panels. Any
direct contact of lines and panels transmits noise
and must be eliminated.

82AIR CONDITIONING
2
REPAIR PERIODIC MAINTENANCE
Routine servicing, apart from visual checks, is not
necessary. The visual inspections are as follows:
Condenser
With a water hose or air line, clean the fins of the
condenser to remove flies, leaves, etc. Check the pipe
connections for signs of oil leakage.
Compressor
Check pipe connections for signs of oil leakage.
Check flexible hoses for swelling. Examine the
compressor belt for tightness and condition.
Sight glass and Receiver/Drier
Examine the sight glass for bubbles with the system
operating. Check connections for leakage.
Evaporator
Examine the refrigeration connections at the unit. If
the system should develop a fault, or if erratic
operation is noticed,
See Fault diagnosis,
Refrigeration System Faults
RECEIVER DRIER
Service repair no - 82.17.01
Remove
CAUTION: If receiver/drier is to be refitted,
the ports must be blanked off immediately
on disconnection. Exposed life of unit is
only 15 minutes.
1.Disconnect battery negative lead.
2.Recover refrigerant from system.
See
Adjustment, Refrigerant Recovery Recycling
Recharging
WARNING: Wear eye and hand protection
when disconnecting components
containing refrigerant. Plug all exposed
connections immediately.
3.Remove 3 screws from bonnet locking platform
and remove radiator grille.
Automatic gearbox
4.Remove 4 bolts securing transmission oil cooler
to body.

AIR CONDITIONING
3
REPAIR 5.Disconnect 2 pipe unions from oil cooler. Use a
second wrench to support hose adapter.
6.Remove transmission oil cooler. Seal
connections.
All models
7.Remove bolt securing receiver/drier clamp.
WARNING: Wear eye and hand protection
when disconnecting components
containing refrigerant. Plug all exposed
connections immediately.
8.Move receiver/drier just sufficiently to gain
access to pipe flange bolts without distorting the
pipes.
9.Remove bolt securing each pipe flange to
receiver/drier.
10.Disengage pipe flanges and withdraw
receiver/drier from mounting bracket.
11.Remove 'O' ring from each pipe flange.Refit
12.Fit new 'O' ring to each pipe flange, lubricate
with refrigerant oil.
13.Position receiver/drier in mounting bracket with
inlet and outlet connections correctly aligned.
14.Engage pipe flanges, fit bolts in turn and tighten.
15.Fit clamp bolt.
Automatic gearbox
16.Refit transmission oil cooler. Use a second
wrench to support pipe unions.
17.Check gearbox fluid level, top-up if necessary.
All models
18.Evacuate and recharge air conditioning system.
See Adjustment, Refrigerant Recovery
Recycling Recharging
19.Perform a leak test on disturbed joints.
20.Carry out a functional check.

82AIR CONDITIONING
4
REPAIR AIR CONDITIONING SWITCH
Service repair no - 82.20.29
Remove
1.Remove fascia centre louvre vent panel.
See
CHASSIS AND BODY, Repair, Dash Panel
Central Louvre Panel
2.Disconnect multiplug from switch
3.From the rear, push switch out of panel.
Refit
4.Reverse removal procedure.DUAL PRESSURE SWITCH
Service repair no - 82.20.20
Remove
1.Disconnect battery negative lead.
2.Recover refrigerant from system.
See
Adjustment, Refrigerant Recovery Recycling
Recharging
3.Disconnect multiplug from switch.
4.Unscrew switch from adapter. Use a second
wrench to support adapter.
WARNING: Wear eye and hand protection
when disconnecting components
containing refrigerant. Plug all exposed
connections immediately.
5.Remove 'O' ring from switch.
Refit
6.Reverse removal procedure. Lubricate new 'O'
ring with refrigerant oil and fit to switch.
7.Screw switch into adapter and tighten to
11 Nm.
8.Evacuate and recharge air conditioning system.
See Adjustment, Refrigerant Recovery
Recycling Recharging

AIR CONDITIONING
5
REPAIR COMPRESSOR
Service repair no - 82.10.20
Remove
1.Disconnect battery negative lead.
2.Recover refrigerant from air conditioning system.
See Adjustment, Refrigerant Recovery
Recycling Recharging
3.Remove screws retaining centre panel to fan
cowl
4.Remove centre panel.
V8i engine illustrated
5.Remove 2 bolts securing hose flanges to
compressor.
WARNING: Wear eye and hand protection
when disconnecting components
containing refrigerant. Plug all exposed
connections immediately.6.Disconnect high pressure hose from
compressor.
7.Disconnect low pressure hose from compressor.
8.Remove 'O' ring from each flange.
9.Disconnect electrical lead from compressor
clutch.
10.Release drive belt from compressor pulley.
See
ENGINE, Repair, Drive Belt
11.Remove 4 bolts securing compressor to
mounting bracket.
12.Remove compressor from mounting bracket.
Refit
13.New compressor to be fitted: Drain oil from new
compressor outlet port. Drain and measure oil
from old compressor. Measure new oil equal to
amount drained from old compressor, add 30 ml
extra to this amount and refill new compressor
through outlet port.
14.Locate compressor in mounting bracket, fit bolts.
Tighten to
25 Nm.
15.Connect electrical lead to compressor clutch.
16.Fit new 'O' rings to high and low pressure hose
flanges, lubricate with refrigerant oil.
17.Engage hose flanges, fit bolts. Tighten to
10
Nm.
18.Fit compressor drive belt.See ENGINE, Repair,
Drive Belt
19.Fit centre panel to fan cowl.
20.Evacuate and recharge air conditioning system.
See Adjustment, Refrigerant Recovery
Recycling Recharging
21.Perform a leak test on disturbed joints.
22.Carry out a functional check.

82AIR CONDITIONING
6
REPAIR CONDENSER
Service repair no - 82.15.07
Remove
1.Disconnect battery negative lead.
WARNING: Wear eye and hand protection
when disconnecting components
containing refrigerant. Plug all exposed
connections immediately.
2.Recover refrigerant from system.
See
Adjustment, Refrigerant Recovery Recycling
Recharging
3.Remove front grille panel.
4.Remove battery.
See ELECTRICAL, Repair,
Battery
5.Remove radiator and oil coolers assembly.See
COOLING SYSTEM, Repair, Radiator
6.Disconnect high and low pressure pipes at
condenser unions.
7.Discard 'O' ring seal from each union.
8.Remove 2 bolts securing condenser to body.
9.Pull condenser into radiator area.
10.Disconnect multiplug from each fan lead.
11.Remove condenser assembly.
Do not carry out
further dismantling if component is removed
for access only.
Blank off inlet and outlet ports.

AIR CONDITIONING
7
REPAIR
12.Disconnect receiver/drier pipes at condenser
unions.
13.Remove retaining bracket from side pipe.
14.Remove LH pipe from condenser and discard 'O'
ring.
15.Remove 2 screws securing receiver/drier
bracket.
16.Release pipes from lower clips and remove
receiver/drier assembly.
17.Remove 'O' ring from RH pipe
18.Remove 2 screws securing lower end of each
fan motor.
19.Remove 2 bolts and remove condenser lower
mounting bracket.
20.Remove 2 bolts and securing condenser upper
mounting bracket.
21.Remove upper mounting bracket and fan motor
assembly.
22.Remove 2 screws securing each side mounting
bracket and remove the brackets.
23.Transfer parts removed to new condenser.
24.Add 40 ml of refrigerant oil to new compressor to
compensate for oil loss.
Refit
25.Reverse removal procedure. 3 to 11.
26.Evacuate and recharge air conditioning system.
See Adjustment, Refrigerant Recovery
Recycling Recharging
27.Carry out leak test on disturbed joints.See
Adjustment, Leak Test System
28.Check air conditioning operation by carrying out
a System Test.
See Adjustment, System Test
CONDENSER FANS AND MOTORS
Service repair no - 82.15.01 - Motor
Service repair no - 82.15.03 - Fan
Remove
1.Remove condenser assembly.
See Condenser
2.Remove 4 bolts securing fan cowl to condenser.
3.Remove 3 bolts securing fan motor to cowl.
4.Remove fan motor assembly.
5.Remove 3 screws securing fan blades to motor.
6.Remove fan blades.
Refit
7.Reverse removal procedure. Ensuring that wiring
is clipped and no fouling of fan blade can occur.

82AIR CONDITIONING
8
REPAIR HEATER AND COOLER UNIT
Service repair no - 86.25.21
WARNING: All work involving the service
and maintenance of air conditioning
requires special equipment, knowledge,
experience and a full awareness and adherence to
safety precautions.
Remove
1.Disconnect battery negative lead.
2.Drain engine coolant.
See COOLING SYSTEM,
Adjustment, Coolant
3.Recover refrigerant from air conditioning system.
See Adjustment, Refrigerant Recovery
Recycling Recharging
4.Remove fascia panel assembly.See CHASSIS
AND BODY, Repair, Dash Panel Assembly
5.Release clips and disconnect coolant hoses
from heater pipes.
6.Remove securing bolt and disconnect low
pressure pipe from evaporator.
WARNING: Wear eye and hand protection
when disconnecting components
containing refrigerant. Plug all exposed
connections immediately.
7.Release 'P' clip retaining high and low pressure
pipes.
8.Remove securing bolt and disconnect high
pressure pipe from evaporator.
9.Discard 'O' ring seals.

AIR CONDITIONING
9
REPAIR
10.Disconnect multiplug connecting heater to
blower unit, remove 3 screws and remove
blower unit.
11.Remove 5 screws securing casing to bulkhead
and tunnel.
12.Remove 2 securing bolts and remove centre
console front mounting bracket.
13.Disconnect 2 drain tubes..
14.Ease heater and cooler unit from its location and
remove from vehicle.
Refit
15.Ease heater and cooler unit into position.
16.Fit retaining bolts finger tight. Tighten in
sequence, centre and top bolts and then the
bottom bolt.
17.Reverse removal procedure.
18.Use new 'O' rings and lubricate with refrigerant
oil.
19.Evacuate and recharge system.
See
Adjustment, Refrigerant Recovery Recycling
Recharging
20.Leak test any disturbed joints.See Adjustment,
Leak Test System
21.Perform a functional check.EVAPORATOR AND EXPANSION VALVE
Service repair no - 86.25.20 - Evaporator
Service repair no - 86.25.01 - Expansion valve
Remove
WARNING: Wear eye and hand protection
when disconnecting components
containing refrigerant. Plug all exposed
connections immediately.
1.Remove heater and cooler unit.
See Heater
and Cooler Unit