Electrical Leak Detector

REFRIGERANT LINES


VK45DE : Electrical Leak Detector


PRECAUTIONS FOR HANDLING LEAK DETECTOR
Use an electrical leak detector (SST: J-41995) or equivalent when performing a refrigerant leakage check. Ensure that the instrument is calibrated and set properly per the operating instructions.





The leak detector is a delicate device. Read the operating instructions and perform any specified maintenance for using the leak detector properly.
1. Position probe approximately 3 mm (0.12 in) away from point to be checked.





2. Circle each fitting completely with probe when testing.
3. Move probe along component approximately 25 to 50 mm (1 to





2 in)/sec.

CHECKING PROCEDURE
Check that there is no refrigerant vapor, shop chemicals, or cigarette smoke in the vicinity of the vehicle to prevent inaccurate or false readings. Perform the leakage test in calm area (low air/wind movement) so that the leaking refrigerant is not dispersed.





1. Stop the engine.
2. Connect a suitable manifold gauge set (SST: J-39183) to the A/C service valves.
3. Check if the A/C refrigerant pressure is at least 345 kPa (3.52 kg/cm2, 50 psi) above 16�C (61�F).
Recover/evacuate and recharge the system with the specified amount of refrigerant if less than specification.

NOTE:
Leakages may not be detected since the system may not reach 345 kPa (3.52 kg/cm2, 50 psi) at temperatures below 16�C (61�F).
4. Perform the leak test from the high-pressure side (compressor discharge "a" to evaporator inlet "h") to the low-pressure side (evaporator drain hose "i" to shaft seal "n"). Refer to Component.
Perform a leak check for the following areas carefully. Clean the component to be checked and move the leak detected probe completely around the connection/component.
Compressor
Check the fitting of high- and low-pressure flexible hoses, relief valve and shaft seal.
Condenser
Check the fitting of high-pressure flexible hose and pipe.
Liquid tank
Check the fitting of refrigerant pressure sensor.
Service valves
Check all around the service valves. Ensure service valve caps are secured on the service valves (to prevent leaks).

NOTE:
After removing A/C manifold gauge set from service valves, wipe any residue from valves to prevent any false readings by leak detector.
Cooling unit (Evaporator)
With engine OFF, turn blower fan on "High" for at least 15 seconds to dissipate any refrigerant trace in the cooling unit. Wait a minimum of 10 minutes accumulation time (refer to the manufacturer's recommended procedure for actual wait time) before inserting the leak detector probe into the drain hose.
Keep the probe inserted for at least 10 seconds. Use caution not to contaminate the probe tip with water or dirt that may be in the drain hose.
5. Verify at least once by blowing compressed air into area of suspected leakage, then repeat check as outlined above if a leak detector detects a leakage.
6. If a leakage is found, but continue checking for additional leakages at all system components.
When leakages are not found, go to next step.
7. Start the engine.
8. Set the A/C control as per the following:
a. A/C switch: ON b. Air flow: VENT (Ventilation)
c. Intake door position: Recirculation d. Temperature setting: Maximum cold e. Fan speed: High
9. Run engine at 1,500 rpm for at least 2 minutes.





10. Stop the engine and perform leakage check again, steps 4 � 6.
Refrigerant leakages should be checked immediately after stopping the engine. Begin with the leak detector at the compressor.
The pressure on the high-pressure side drops gradually after refrigerant circulation stops and pressure on the low-pressure side rises gradually, as shown in the graph. Some leakages are more easily detected when pressure is high.
11. Check recovery/recycling recharging equipment gauges before connecting recovery/recycling recharging equipment to vehicle. No refrigerant pressure should be displayed. Recover refrigerant from equipment lines if pressure is displayed.
12. Confirm refrigerant purity in supply tank using recovery/recycling recharging equipment and refrigerant identifier.
13. Confirm refrigerant purity in vehicle A/C system using recovery/recycling recharging equipment and refrigerant identifier.
14. Discharge A/C system using approved refrigerant recovery equipment. Repair the leaking fitting or component if necessary.
15. Evacuate and recharge A/C system and perform the leakage test to confirm no refrigerant leakages.
16. Perform A/C performance test to ensure system works properly.