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4.3
Audio and visual outputs
The Gas Check 5000is series have an internal audio sounder and a flashing LED indicator.
They both operate together when the detected leak rate climbs from the zero indication towards the
maximum on the leak rate range (see Section 4.2.1). They also operate once to confirm a key press.
4.4
Prepare the Gas Check
4.4.1 Select which probe to use
Note: Whenever possible, use the Gas Check with the nozzle fitted. The nozzle helps to protect the
short probe from blockage or damage. You cannot use the nozzle with the long probe.
Open the storage case and remove the Gas Check. The Gas Check is supplied with the short probe
fitted and the nozzle fitted; a long probe is supplied in the storage case. Determine whether you
want to use the short probe or the long probe and whether you want the nozzle fitted, as follows:
·
Use the Gas Check with the short probe and without the nozzle to detect small leak rates of
approximately 1 x 10
–4
ml/sec and lower. Press the nozzle key to clear the nozzle fitted indicator:
refer to Section 4.1
·
For large leaks, use the Gas Check with the short probe and the nozzle fitted. The nozzle extends
the detection range for more accurate measurement of large leaks. Press the nozzle key to set
the nozzle fitted indicator: refer to Section 4.1.
·
If the area you want to leak check has restricted access, remove the nozzle and the short probe
and fit the long probe. The long probe is flexible and can be bent in a gentle arc so that it can
reach areas that would otherwise be difficult to reach. Press the nozzle button to tell the Gas
Check that the nozzle is not fitted when you fit the long probe: refer to Section 4.1/ Note that
response time increases significantly when the long probe is fitted (see the note in Section
4.6.1).
The nozzle simply pulls off and pushes onto the end of the Gas Check. To remove the nozzle or to
change the probe, refer to Section 4.4.2.
4.4.1
Remove the Gas Check nozzle or change the probe (if required)
1
Switch off the Gas Check.
2
Refer to Figure 5. If the nozzle is fitted, hold the nozzle (1) by its wide base and gently twist and
pull it to remove it from the Gas Check.
3
With the small end of the box spanner towards the Gas Check, guide the end of the probe (2 or
7) through the middle of the box spanner. Push the box spanner onto the nut (3) and turn the
box spanner anticlockwise to undo and remove the probe.
4
Push the probe insert (4) of the other probe into the sample hole in the probe/nozzle fitting (5),
then tighten the nut (3) one or two turns by hand to loosely secure the probe.
5
With the small end of the box spanner towards the Gas Check, guide the end of the probe
through the middle of the box spanner. Push the box spanner onto the nut (3) and turn the box
