HVAC: Overview Subaru Forester SG

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1. AUTO A/C MODEL
2. MANUAL A/C MODEL

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1. AUTO A/C MODEL Tightening torque: N.m (kgf-m, ft-lb) T: 7.5 (0.76, 5.5)
2. MANUAL A/C MODEL Tightening torque: N.m (kgf.m, ft-lb) T: 7.5 (0.76, 5.5)

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1. AUTO A/C MODEL
2. MANUAL A/C MODEL

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1. AUTO A/C MODEL
2. MANUAL A/C MODEL

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Tightening torque: N.m (kgf-m, ft-lb)

1. T1: 7.4 (0.75, 5.4)
2. T2: 15 (1.5, 10.8)

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Tightening torque: N.m (kgf-m, ft-lb)

1. T1: 4.0 (0.40, 2.95)
2. T2: 22.6 (2.3, 16.6)
3. T3: 23.0 (2.35, 17.0)
4. T4: 28.9 (2.95, 21.3)
5. T5: 35 (3.6, 26)

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1. Unlike the old conventional HFC-12 system components, the cooling system components for the HFC-134a system such as the refrigerant and compressor oil are incompatible.
2. Vehicles with the HFC-134a system can be identified by the label "A" attached to the vehicle. Before maintenance, check which A/C system is installed in the vehicle.

OPERATION

1. Place the vehicle in the shade and draftless condition.
2. Connect the manifold gauge set.
3. Open the front windows and close all doors.
4. Open the hood.
5. Increase the engine to 1,500 rpm.
6. Turn ON the A/C switch.
7. Turn the temperature control switch to MAX COOL.
8. Put in RECIRC position.
9. Turn the blower control switch to HI.
10. Read the gauge. Standard: Low pressure: 127 - 196 kPa (1.3 - 2.0 kg/cm 2 , 18 - 28 psi) High pressure: 1,471 - 1,667 kPa (15 - 17 kg/cm 2 , 213 - 242 psi) Ambient temperature: 30 - 35 °C (86 - 95 °F)

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1. Perform the compressor oil return operation. Refer to «OPERATION»(ref-200802-S42441765782005102300000) , Compressor Oil.
2. Stop the engine.
3. Make sure the valves on low-/high-pressure sides of manifold gauge set are fully closed.
4. Install the low-/high-pressure hoses to the service ports on the low-/high- pressure sides of the vehicle respectively.
5. Connect the center hose to the refrigerant recovery system.
6. Follow the operation manual to activate the refrigerant recovery system.

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1. Close all valves of manifold gauge.
2. Install the low-/high-pressure hoses to corresponding service ports on vehicle. CAUTION: Be sure that the hoses are securely connected.
3. Connect the center hose of manifold gauge with vacuum pump.
4. Activate the vacuum pump and then open the valves on low-/high-pressure sides. CAUTION: Be sure to evacuate the system using vacuum pump.
5. After at least 5 minutes of evacuation, if the low-pressure gauge reading shows 100.0 kPa (750 mm Hg, 29.5 in Hg) or higher, close the valves on center hose to stop the vacuum pump.
6. Leave it at least 5 to 10 minutes after closing the valves on low-/high- pressure sides, and then check the low-pressure gauge reading for any changes. When the gauge reading changes, this is a sign of leakage. Check the pipe or hose connector points, and repair if necessary. Repeat the procedure from 1) after repairing the faulty part.
7. If there are no leaks, further evacuate the system 20 to 30 minutes.
8. Close all valves and stop the vacuum pump.
9. Following the can tap operation manual instructions, install it to refrigerant can.
10. Disconnect the vacuum pump from center hose, and connect the hose to tap valve.
11. When a refrigerant recovery container is used, measure the refrigerant amount in use using a weighting scale before connecting to center hose.
12. Open the valve on HFC-134a source.
13. Loosen the center hose connection on manifold gauge (if applicable, press a purge valve on manifold gauge) only for a couple of seconds to allow the air in the center hose to escape by the refrigerant.
14. Make sure that the high-pressure valve of manifold gauge is closed, and then open the low-pressure side valve only to charge the refrigerant. CAUTION: Do not open the high-pressure valve. Be sure to open the low-pressure valve.
15. Close the low-pressure valve when the low-pressure gauge reading reaches 200 kPa (1,500 mm Hg, 59.1 in Hg).
16. Using a leak tester, check the system for refrigerant leaks.
17. After confirming that there are no leaks with the leak test, charge the required amount of refrigerant.
18. If the HFC-134a source is empty, close the low-pressure valve and then close the valve on can tap before replacing the empty source. Restart charging operation after replacing the HFC-134a source with a new one and purging.
19. Close the low-pressure valve if the charge rate of refrigerant becomes worse.
20. Confirm that both the low-/high-pressure valves are closed. Start the engine with A/C switch OFF.
21. Quickly repeat A/C switch ON-OFF cycles a few times to prevent initial compressor damage.
22. Set up the vehicle to the following status: A/C switch ON Engine running at 1,500 rpm Blower speed setting to "Hi" Temperature setting to "MAX COOL" Air inlet setting to "RECIRC" Window open
23. Open the low-pressure valve and charge the specified amount of refrigerant.
24. Close all valves and disconnect the hoses from service port after charging the refrigerant.
25. Install the cap to service port.

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1. Operate the A/C system for approx. 10 minutes, and confirm that the high-pressure side shows at least 690 kPa (7.03 kg/cm 2 , 100 psi). Then stop the engine to start the leak test.
2. Starting from the connection between the high-pressure pipe and evaporator, check the system for leaks along the high-pressure side through the compressor. The following items must be checked thoroughly.
3. Check the joint and seam between the pressure switch (triple pressure switch) and high-pressure pipe.
4. Check the connections between the condenser and pipes, and welded joints on the condenser. The leak tester may detect the oil on the condenser fins as a leak.
5. Check the joint between the compressor and hoses.
6. Check the machined area of compressor and other joints on the compressor.
7. Check the compressor shaft seal at the area near the center of compressor clutch pulley. Some shaft seals show a slight amount of leakage about 28 g (1.0 oz) per year. This is not a problem.
8. Starting from the connection between the low-pressure pipe and evaporator, check the system for leakage along the low-pressure side through the compressor. The following items must be checked thoroughly. Connection between two parts Connection between the pipe and plate
9. Visually check the rubber area of the flexible hose for cracks. Check the entire length of the flexible hose, especially the connection with the metal hose end. CAUTION: Carefully check the external surface of hoses and tubes at approx. 25 mm (0.98 in) per second.
10. Disconnect the drain hose from the heater case, and check the hose end for at least 10 seconds. After the test is finished, reconnect the drain hose.
11. Turn the ignition key to ON position, and run the blower at high speed for 1 minute. Stop the blower to check the ventilation grille on the instrument panel. While moving the tester closer to the grille, run the blower for 1 or 2 seconds, then stop it. Check the grille at that point for at least 10 seconds.
12. Check the valve in the service port.
13. Visually check the rubber seal in the service port cap.

Note. Before making repairs, conduct the oil return operation to return the compressor oil in circulation with the refrigerant to the compressor.

1. Increase engine to 1,500 rpm.
2. Turn ON the A/C switch.
3. Turn the temperature control switch to MAX COOL.
4. Put in RECIRC position.
5. Turn the blower control switch to HI.
6. Leave in this condition for 10 minutes.