AMI Analyzer Manual
Maintenance and troubleshooting
29
Bleeding a regulator
A newly installed regulator on a bottle of span gas is of course filled with air, at 210,000 ppm of Oxygen.
Until this air is removed, the apparent oxygen concentration in the span gas will be much higher than it
should be. While simply flowing the span gas could take days to purge the trapped oxygen, it is much
quicker and more reliable to “Bleed” the regulator first.
1. Install the regulator on the span gas bottle, but do not open the bottle valve yet.
2. If the regulator has a shut off valve on its output side, close it.
3. Briefly open the bottle valve (to pressurize both side of the regulator), and close it again.
4. Use “Snoop
” or equivalent to completely leak-check the regulator, gauges, fittings and bottle valve.
5. Loosen the nut connecting the regulator to the bottle and allow the high pressure gauge to bleed off to
zero, and then immediately tighten it again.
6. Open the regulator to its full pressure.
7. Repeat steps 3 and 5 seven to ten times.
8. Set the regulator to its correct output pressure (typically 10 psig).
9. Close the bottle valve.
10. Open the output shut off valve located on the low pressure side of the regulator until both gauges drop
to zero.
11. Close the shut off valve.
12. Open the bottle valve.
13. Repeat steps 9, 10 and 11 seven to ten times.
14. Now open the bottle valve, and the shut off valve, and allow gas to flow through the tubing to the
analyzer for two minutes before tightening the compression fitting on the analyzer..
