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10.2 Periodic maintenance and inspection
Procedure
Refer to section 8.5 to 8.6.
It takes at least 1.5 months to deliver the standard gas. So
the gas should be ordered 2 or 3 months in advance.
Supply water if level is below overflow port.
Replace with new filter paper (stop the aspirator when
exchanging). See 10.5 (3).
Replace these parts if flow rate doesn’t increase because of
adherence of dust. See 10.5 (2).
Replace if clogged.
Check and clean diaphragm. Use valve by turning it to 90°
rightward (replace valve when it is turned once). See 10.5
(4).
Apply soapy water or the like and check for bubbles. Either
retighten or replace packings if necessary.
NO, SO
2
, CO/N
2
of less than 250 ppm. See 10.4.
O-ring requires replacement. Filter element may be reusable
after cleaning. See 10.5 (1).
Replacement (when NO
2
gas concentration is 10 ppm or
less)
Note: Replace once every 8 months when NO gas con-
centration is measured in the setting range of 0 to
200ppm or more at 0.5L/min.
See 10.4.
Replacement of diaphragm
Clean pipes or replace if necessary.
Maintenance/inspection item
Analyzer calibration
Check of standard gas filled
pressure
Water level in upper chamber of
conditioner
Replacement of membrane filter
paper
Inspection and replacement of
conditioner filter, O-ring
Capillary
Check of valve and diaphagm of
aspirator (pump)
Leak test of pressure regulator
Replacement of standard gas
Replacement of gas extractor filter
element, O-rings
Catalyst of NO
2
/NO converter
Replacement of standard gas
Aspirator
Contamination, leak test of piping
Exchange of water in conditioner
Overhaul
Referential frequency
Weekly
Monthly
Every two months
Biannually
Yearly
10.3 Other maintenance and inspection
(1) Space heater and ventilating fan
If the ambient temperature drops below 5°C during winter or the like, then turn ON the space heater.
The ventilating fan should always be left ON.
(2) Blowback of gas extractor (option)
Turn off the aspirator and close the measured gas line before conducting a blowback. Frequent blowback
will cause the temperature of the gas sampler to drop and result in corrosion, so it should be kept to a
minimum.