Teledyne 6750, Operating Instructions Manual, Page: 72 / 96

Maintenance Model 6750
Teledyne Analytical Instruments
60
Figure 5-11: Mass Flow Controller
5.3.10 Metering Valve (P/N ST16050)
If no O
2
/air flow to the sparger (P/N ST20025) is observed (no
bubbles), check for tubing and fitting leaks, restrictions and adjust
metering valve (be careful to return to previous indicated bubble rate).
If flow cannot be restored, replace the metering valve (P/N ST16050)
according to the directions below. See Figure 5-12.
To replace the metering valve:
1. Turn carrier gas (Air/O
2
) OFF.
2. Turn pumps OFF.
3. Remove fittings and tubing.
4. Remove metering valve.
5. Recalibrate TIC if TIC and/or TOC–TRUE analysis is
required. NPOC analysis only does not require
recalibration.
6. Reinstall metering valve in reverse order.