Leak Check Procedure - Teledyne 6400A Instruction Manual

TAI Model 6400A SO

8.8 Leak Check Procedure

There are two methods of leak checking. First one is the vacuum method which is simplest but it
does not show the location of a leak. This vacuum method described below is the general method
when a Leak Checker (refer to Figure 9-10) is not readily available. The second method is using
pressure and this method can be used to find the exact location of a leak by using bubble
solution.
Vacuum method:
1. Cap the sample inlet port(plug zero air scrubber inlet also if it is installed).
2. Remove the inlet fitting from the pump.
3. Set the TEST function to SAMP FL. Record the reading.
4. Reinstall the inlet fitting of the pump and check the sample flow reading. It should be
close(±20 CC/min.) to the previous reading in step 4.
After step 1 of above, pull the vacuum for about 15 in-Hg and close the shut off valve of the leak
checker. If the pressure changes more than 1 in-Hg within 5 minutes, there is a leak. It is not
possible by the vacuum method to tell where the leak is located. See the pressure method below
to locate the leak.
Pressure method:
5. Set up Simple Leak Checker as shown in Figure 9-11 or similar one between the pump and
exhaust line that is connected to the pump. (Refer to Figure 8-3 for pneumatic diagram.)
6. Swap the inlet and outlet of the pump so that the pump pressurizes instead of pulling
vacuum.
7. Adjust needle valve such that the gauge pressure does not exceed 15 PSIG.
8. Apply bubble solution to all the seals, interfaces and fittings to locate the leak.
9. Tighten the seal or fitting until the leak stops.
Lastly, drop off any accumulated bubble solution and properly reinstall the inlet and outlet fittings of the
pump.
Analyzer Operator Manual, 02164, Rev. G
2
Do not use bubble solution during vacuum method as
the solution may enter and contaminate the cell.
NOTE
8-9