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Teledyne 6750 - Total Organic Carbon analyzers User Manual

Page 72

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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.