DACIA SUPERNOVA 2004 Repair Manual

AIR CONDITIONING
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AC UN
IT OPERATING DIAGRAM
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Basically, the air conditioning unit is formed of a closed circuit, composed by the following main
elem ents:
- ev aporator
- compre ssor
- c ondenser
- thermo static expansion valve
- conn ection pipes.
The evaporator is the component that ex t racts the heat from the passengers compartment and
is generally placed in the passengers compartment. In order to cool the passengers compartment
the hot air must be absorbed, the heat extracted and the “cooled” air redistributed. The hot air is
pa ssing through the evaporator to who is giving part of the temperature reducing so, its own
temperature. The cooled air is so conveyed in the passengers compartment, progressively reducing
the temperature.
In the same time, the refrigerant fluid which goes into the evaporator, is absorbing the heat, from
ai r pa ssing through the evaporator and at the same temperature, is transforming it from liquid into
va pors. At the evaporator exit, the refrigerant fluid is in vapor condition.
The evaporator is placed in the climate control unit and is protected by cases.
EVAPORATOR
EVAPORATOR CASES ASSEMBLY REPLACEMENT
DISMOUNTING
Disconnect the battery.
Drain the refrigerant circuit.
Dismount the sealing gaskets on the climate box outliner.
Dismount the thermostatic expansion valve.
Dismount the climate case locking plate.
Di sconnect the pipes evaporator – compressor and evaporator – tank filter.
Dismount the evaporator cases attachment nuts, on the right side.
Release the evaporator cases.
Replace the assembly .
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REMOUNTING
Perform the dismounting
operations in the reverse order.
Fill the refrigerant circuit and check the good operation of the climate control system.
NOTE
Ensure that evaporator finned plates are not deformed and they are not excessive
dirty.
The tightening nuts for the climate and conditioning assembly, the connections for piping,
condenser and filter tank, must have the following tightening moments:
- thread 3/4” – 16 pitch/l” – at t he moment 18-20 Nm;
- thread 5/8” - 18 pitch/l” – at the m oment 14-20 Nm.
The tightening moment of the compressor flange attachment screw -12+/-1,2 Nm.
The tightening moment of the thermostatic probe attachment screw -5,7+/-0,5 Nm.
The tightening moment of the pressure capture - 20,7+/-2 Nm.
NOTE
After each operation that implies t he disconnection of t he battery, at its reconnection,
introduce the radio code that is written on the vehicle-selling invoice. EVAPORATOR
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The compressor is absorbing the vapors coming from the evaporator at low pressure and
temperature, is compressing them and convey the gas at high temperature and pressure. The refrigerant fluid in high pressure and temperature vapor condition is entering in the second
he at exchanger, which by condensation is transmitting the heat to the external environmental.
At the exit from the condenser, the refrigerant fl uid is in liquid condition, at a high pressure and temperature.
Type of compressor: SD 7Y15
Compressor oil : PAG SP 10 or SP20, volume –135 cmc.
Refrigerant: HFC 134 a, quantity of refrigerant : 0.590 kg
C OMPRESSOR REPLACEMENT
DISMOUNTING
Disconnect the battery.
Drain the refrigerant circuit.
Disconnect the compressor’s connection.
Disconnect the pipes from the compressor.
Dismount the belt tensioning screw and release the belt.
Dismount the compressor attachment screws.
Dismount the compressor.
Replace the compressor.
REMOUNTING
Perform in the reverse order the dismounting operations.
T ension the belt and tighten at the required moment the tightening attachment screw.
Fill the refrigerant circuit and check the good operation of the climate control system.
COMPRESSOR
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THE CONDENSER
The condenser is placed on the cooling radiator, in the front part of the vehicle and is ensuring
the exhaust of the refrigerant heat accumulated at compression.
In order to grant the optimum condenser operation, frequently check if its outside surfaces are
always clean and the air penetration is not stopped. Also, check the condenser pipes in order not
to show deformations. CONDENSER
CO
NDENSOR REPLACEMENT
DISMOUNTING
Disconnect the battery.
Drain the cooling circuit.
Dismount the pipes connected to the condenser.
Dismount the radiator-condenser assembly.
Separate t he cooling radiator from the condenser.
ATTENT ION:
A void the possible deformation of t he ducts and fi nned plates.
Replace the condenser.
REMOUNTING
Perform the dismounting operations in the reverse order.
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PRESSURE CONTROLLER
(low pressure, high pressure, medium pressure, in accordance
with the specification) or pressure capture
- low pressure – disconnect when the pressure in the low pressure circuit is lower than
1,96 +/-0,2 bar , reestablishing at a higher pressure than 2,16 +/- 0,2 bar; - higher pressure – disconnect when the pressure in the high pressure circuit is higher than
31,4 +/-2 bar , reestablishing at a higher pre ssure than 25,5 +/-2 bar; - medium pre ssure - start s the bl ower on t he second level speed, when t he pressure i s
higher than 17,7+/-1bar and stops the blower at a lower pressure 13,7+/- 1,2.
Thermostatic expansion valve allows the reduction of the refrigerant liquid pressure which is
coming from t he condenser, passing through the tank filter and i s continuously adjusting the
refrigerant flow from the evaporator, to reach the compressor in vapor condition. PRESSURE CONTROLLER
The good operation of the air conditioning unit is ensured by a dryer filter tank that ha s the
purpose to protect the unit. The filter’s purpose is to absorb the eventually solid particles found
in the oil and refrigerant liquid circulation.
The interception is needed as they might block the operation of the thermostatic expansion
valve or may produce the compressor mobile parts worn or gripping.
DETECTION OF REFRIGERANT F LUID LEAKAGE
In order to detect the refrigerant liquid leakage, it is used a detector, calibrated to detect
leakage of 9gr. /year.
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DRY
ER FILTER TANK
The dryer filter tank has a triple function in the air conditioning unit:
- filtering the refrigerant fluid from the unit;
- absorbing the moisture from the unit;
- it is a buffer storage tank of refrigerant fluid.
DRY ER FILTER TANK
REMOUNTING
Perform the dismounting operations in the reverse order.
Fill the refrigerant circuit, check the leakage and the good operation of the unit.
AT TENT ION
Do not mount dryer fi lter tanks that do not have protection covers. DRY
ER FILTER TANK REPLACEMENT
DISMOUNTING
Disconnect the battery.
Drain the refrigerant circuit.
Dismount the piping and protect the threads.
Disconnect the connector of the air conditioning pressure controller.
Dismount the receiver tank filter from the collar support.
Replace the tank filter.
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UNIT PIPING
The air conditioning unit piping is ensuring the refrigerant fluid circulation between the unit
components. When piping is replaced, check the existence of the protective covers, the lubrication
of the connections and gaskets with compressor oil as well as filling up with compressor oil.
The unit filling and draining valves are placed on the compressor piping and they have different
diameters, so that they can not be reversed.
NOTE
For tightening or loosening the unit piping connections where the refrigerant fluid is
passing through, two special wrenches are to be used, in order to balance the moments’ twist.
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CL
IMA TE CONTROL UNIT REPLACEMENT
DISMOUNTING
Disconnect the battery.
Release t he lateral and central console.
Disconnect the wires from the dashboard wiring.
Disconnect the distribution flow flap control cables and the mixing flow flap from the control
lever and the recycling flow flap cable from the climate control panel.
Disconnect the air flow pipes.
Dismount the screws from the front side of the climate box.
Dismount the nuts from the welded screws in the backside of the climate box.
Release the climate control unit.
Replace the climate control unit.
REMOUNTING
Perform in the reverse order the dismounting operations.
CL
IMA TE CONTROL UNIT
AIR INLET ASSEMBLY REPLACEMENT
DISMOUNTING
Dismount the sealing gaskets on the climate box outliner.
Dismount the climate box locking plate.
Dismount the nuts from the right side of the climate box.
Release the air inlet assembly .
Replace the assembly .
REMOUNTING
Perform in the reverse order the dismounting operations.
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Defective cooling
Is climate
blower working ?
Check the bl ower fuse and relay.
Are they defective?
Supply the blower motor
at (+12 V).
D oes it works?
Replace the climate control
switch or repair the electric
circuit.
Replace them
No
Ye s
Ye s
Change
blower.
No
No
Adequate air flow ?
Check t he a irflow fl aps
operation and the air ducts
integrity.
Compressor belt tensioning is good?
Yes Ye s
No
Any refrigerant fluid leakage
in the system ?
No
Ye s
Ye s
Is compressor clutch supplied with (+ 12 V)?
No
Ye s N o
Clutch is coupling the
compressor?
Replace the therm ostatic
expansion valve.
Ye s
No Check the electri c circ uit
for supplying and control.
Detect th
e refri ge ra nt fl ui d
leakage cause . Perform refilling.
Pressure controller is working?
Replace it.
Reface
i tensiunea curelei
Replace it.
No
Ye s DIAGNOSIS
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