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How to locate leaks
1. Use the SCANNING MODULE.
2. Start off with the sensitivity selection at 0 (Maximum).
3. Begin to scan by pointing the module towards the test area. The procedure is to go from the
"gross" to the "fine" more and more subtle adjustments will be made as the leak is
approached.
4. If there is too much ultrasound in the area, reduce the sensitivity setting and continue to
scan.
5. If it is difficult to isolate the leak due to competing ultrasound, place the RUBBER
FOCUSING PROBE over the scanning module and proceed to scan the test area.
6. Listen for a "rushing" sound while observing the meter.
7. Follow the sound to the loudest point. The meter will show a higher reading as the leak is
approached.
8. In order to focus in on the leak, keep reducing the sensitivity setting and move the instrument
closer to the suspected leak site until you are able to confirm a leak.
B. To confirm a leak
Position the Scanning Module, or the rubber focusing probe (if it is on the scanning module) close
to the suspect leak site and move it, slightly, back and forth, in all directions. If the leak is at this
location, the sound will increase and decrease in intensity as you sweep over it. In some instances,
it is useful to position the rubber focusing probe directly over the suspect leak site and push down
to "seal" it from surrounding sounds. If it is the leak, the rushing sound will continue. If it is not the
leak site, the sound will drop off.
C. Overcoming difficulties
Competing Ultrasounds If competing ultrasounds make it difficult to isolate a leak, there are two
approaches to be taken:
a. Manipulate the environment. This procedure is fairly straight forward. When possible, turn off
the equipment that is producing the competing ultrasound or isolate the area by closing a
door or window.
b. Manipulate the instrument and use shielding techniques. If environmental manipulation is not
possible, try to get as close to the test site as possible, and manipulate the instrument so
that it is pointing away from the competing ultrasound. Isolate the leak area by reducing the
sensitivity of the unit and by pushing the tip of the rubber focusing probe up to the test area,
checking a small section at a time.
