Rover DEFENDER 300Tdi, Workshop Manual

Page: 372 / 450

82
AIR CONDITIONING
2 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 ..........................................................
Evaporator 80ml ..........................................................
Pipe or hose 20ml ........................................................
Receiver/drier 20ml ......................................................
Total quantity of refrigerant oil in system = 140ml
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
A new compressor is supplied with an oil fill of 140ml.
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 (Yml).
4. Calculate the quantity (Qml) of oil to be drained
from the NEW compressor using the following
formula:
Xml - (Yml + 20ml) = Qml
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 90ml 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
Therm20
°
C to -60
°
C
Safety goggles and gloves