Service Procedure

Be aware of the following basic information covering the sensor, filters, and calibration bottle included with the J 39400:

Filter

The filter in the tip of the J 39400 protects the pump and sensor from dust and moisture. With the high sensitivity of the J 39400, you need never touch any surface with the tip to locate the leak. Replace the filter often, and immediately if it comes in contact with moisture or is visibly dirty. Use the following schedule.

Occasional Use: Change Weekly
Regular Use: Change Daily

Keep plenty on hand. Use the black rubber probe tip that came with the detector to keep the filter away from accidental contact with the surface under test.

Calibrated Leak Bottle

This bottle simulates the smallest leak you need to detect. You need to calibrate each time you use the leak detector.

Important:
NEVER OPEN THE LEAK BOTTLE. THE LEAK BOTTLE IS ACTIVATED WHEN YOU REMOVE AND DISCARD THE BLACK ADHESIVE DOT ON THE TOP OF THE CAR IF YOU HAVE REMOVED THE INTERNAL WHITE SEAL, YOU HAVE DESTROYED THE ACCURACY OF THE LEAK AND YOU WILL NEED A REPLACEMENT.

NEVER EXPOSE THE J 39400 TO THE LIQUID REFRIGERANT IN THE BOTTLE WITHOUT THE CAP IN PLACE.

Sensor

Increase the life of your sensor: Use the lowest heater adjustment setting at which the J 39400 detects the calibration leak. Increase heater adjustment setting only when the J 39400 does not respond to the calibration leak bottle. Never calibrate with anything other than the calibrated leak bottle. NEVER INTENTIONALLY EXPOSE THE DETECTOR TO A BLAST OF REFRIGERANT, SUCH AS FROM AN OPEN SCHRADER VALVE.

Advice for Trouble Free Operation - Some Do's and Don'ts:

^ Don't press the probe up against a surface under test.
^ Don't intentionally pull liquids into the probe.
^ Don't block the air flow in the probe, the sensor momentarily overheats and will false alarm.
^ Don't poke foam insulation with the probe. The foam contains refrigerant gas and the J 39400 will detect this as a leak.
^ Do keep plenty of spare filters on hand.
^ Do change the filter often, daily if necessary.
^ Do trust the results of the J 39400. It can only detect halogen gas and will not alarm on any other gas.
^ Do use all three settings on the J 39400. Think of the labels "Gross", "R12" and "R134a" as three separate sensitivity settings for "Large", "Medium", and "Small". You can detect R12 or R134a on any of these settings.

Detecting Gross Leaks with the J 39400: Always use compressed air liberally to blow out residual gas before attempting to pinpoint gross leaks. Place the leak size switch in the "Gross" position. The leak detector will respond to both R12 and R134a leaks in this position. You may have to work in stages, getting closer to the leak gradually because the escaping gas will fill the area under test quickly. Clear out trapped gas in the area to be tested with shop air. Use the balance control on the J 39400 to obtain a slow click rate while the probe is in the contaminated area. The J 39400 has enough resolution to locate the higher gas level at the source of the leak, as long as you can blow out the area first.

After you locate and repair the gross leak, make sure to test the complete system again. You will probably pick up other smaller leaks you could not find in the high background caused by the gross leak.

REMEMBER, if you perform simple maintenance tasks on the J 39400, you can:

^ extend the life of the sensor
^ ensure the quick location of leaks
^ verify a system to be leak free
^ find leaks faster
^ and, you will reduce comebacks.