TELEDYNE API T200U NOy, Operator'S Manual

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Model T200U NOy Option Manual Addendum
24 07303E DCN7996
6.2 Replacing the Sample Particulate Filters
The particulate filter should be inspected often for signs of plugging or
contamination. It is also common for dirt particles to cause instrument drift, and
affect accuracy.
To check and change the filter:
1.
Fold down the 501 NOy front panel.
2. Locate both filters on the left and right side of the 501 NOy front panel. See
Figure 3 for an exploded view of the filter assembly.
3. Visually inspect the filter through the glass window.
4. If the filter appears dirty, unscrew the hold-down ring, remove the Teflon o-ring
and then the filter.
5. Replace the filter, being careful that the element is fully seated in the bottom
of the holder. Replace the Teflon o-ring (refer to Figure 3 for orientation of o-
ring with cutouts), then screw on the hold-down ring and hand tighten. Do not
overtighten; this can cause the glass window to crack!
NOTE
Handle the filter assembly wetted surfaces (glass window, Teflon holder) as little as possible
and clean with cloth prior to assembly