AC 7490
value will be displayed once the leak source has been located. The table below can be used to approximate the
size of leak:
Max displayed
1 -3
4-6
7-9
Low battery
Replace the 4 AA Alkaline batteries when the red LED on the control panel is lit. Follow battery installation
instructions under Maintenance section.
Audio mute system
To silence or mute the audio beep and alarm signal, press the MUTE button. To restore the audio sound, press the
MUTE button again.
Note: a few seconds is required to restore sound if the mute button is pressed in rapid succession.
Adjusting sensitivity levels
The Leak Detector will default to the NORM sensitivity level automatically once the unit cornes out of the warm up
cycle and the green LED will turn on.
To change sensitivity levels, press the SENS once for Hl sensitivity (red LED will turn on) and again for LO sensitivity
(yellow LED will turn on).
Verifying proper operation of detector
The AC 7490 includes a Leak Test Vial that allows the user to make sure the detector is performing properly.
To test:
1. Remove the colored label dot in the center of the screw cap to expose the vent hole in the top of the screw cap.
(see g. below)
2. Turn on the detector and allow the unit to complete the warm up cycle.
3. Place the sensor close to the small hole in the top of the Leak Test Vial. The beep rate should increase and the
Digital Leak Size lndicator should display a number from 3-6 indicating that the sensor and electronics are working
properly.
NOTE: Store the Test Vial in the nylon bag when not in use to extend the shelf life. Replace Test Vial when the green
coloris less than ¼ full or at the time of the expiration date.
ELECTRONIC LEAK DETECTOR FOR NITRO-TRACE TESTING (N2-H2)
Approx. leak size (oz/an)
<0.1
0.1 à 0.5
>0.5
Approx. leak size (g/an)
<3
3 à 14
>14