Electronic Refrigerant Leak Detector
REFRIGERANT LINES
Electronic Refrigerant Leak Detector
PRECAUTIONS FOR HANDLING LEAK DETECTOR
When performing a refrigerant leak check, use an A/C electrical leak detector (SST) or equivalent. Ensure that the instrument is calibrated and set properly per the operating instructions.
The leak detector is a delicate device. In order to use the leak detector properly, read the operating instructions and perform any specified maintenance.
1. Position probe approximately 5 mm (3/16 in) away from point to be checked.
2. When testing, circle each fitting completely with probe.
3. Move probe along component approximately 25 to 50 mm (1 to 2 in) per second.
CHECKING PROCEDURE
To prevent inaccurate or false readings, make sure there is no refrigerant vapor, shop chemicals, or cigarette smoke in the vicinity of the vehicle. Perform the leak test in calm area (low air/wind movement) so that the leaking refrigerant is not dispersed.
1. Turn engine OFF.
2. Connect a suitable A/C manifold gauge set to the A/C service ports.
3. Check if the A/C refrigerant pressure is at least 345 kPa (3.45 bar, 3.52 kg/cm2, 50 psi) above 16�C. If less than specification, recover/evacuate and recharge the system with the specified amount of refrigerant.
NOTE:
At temperatures below 16°C, leaks may not be detected since the system may not reach 345 kPa (3.45 bar, 3.52 kg/cm2, 50 psi).
4. Perform the leak test from the high-pressure side (compressor discharge a to evaporator inlet f) to the low-pressure side (evaporator drain hose g to shaft seal k). Locations. 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, refrigerant pressure sensor.
- Liquid tank
Check the refrigerant connection.
- 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. If a leak detector detects a leak, verify at least once by blowing compressed air into area of suspected leak, then repeat check as outlined above.
6. Do not stop when one leak is found. Continue to check for additional leaks at all system components.
If no leaks are found, perform steps 7-10.
7. Start engine.
8. Set the heater A/C control as follows;
a. A/C switch: ON
b. Mode control dial position: VENT (Ventilation)
c. Intake door lever position: Recirculation
d. Max. cold temperature
e. Fan speed: High
9. Run engine at 1,500 rpm for at least 2 minutes.
10. Turn engine off and perform leak check again following steps 4 through 6 above.
Refrigerant leaks should be checked immediately after stopping the engine. Begin with the leak detector at the compressor. The pressure on the high-pressure side will gradually drop after refrigerant circulation stops and pressure on the low-pressure side will gradually rise, as shown in the graph. Some leaks are more easily detected when pressure is high.
11. Before connecting recovery/recycling equipment to vehicle, check recovery/recycling equipment gauges. No refrigerant pressure should be displayed. If pressure is displayed, recover refrigerant from equipment lines.
12. Discharge A/C system using approved refrigerant recovery/recycling equipment. Repair the leaking fitting or component if necessary.
13. Evacuate and recharge A/C system and perform the leak test to confirm no refrigerant leaks.
14. Perform A/C performance test to ensure system works properly.