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TUBING REPLACEMENT
The remaining tubing in the analyzers should be replaced
every two months.
When installing new tubing it is helpful to dip them in hot
water before making the connections.
It is also recommended that one tube at a time is removed
and replaced.
Note DPD reagent tubing may darken before the scheduled
replacement time, but this will not affect the instrument’s
performance.
CLEANING MEASUREMENT CELL
In order to maintain the maximum reliability of measurements,
it is recommended to periodically clean the measurement cell.
In fact, the measurement cell could collect sediment or de-
velop a film growth on the inside walls.
Thorough cleaning with a dilute acid solution and a cotton
swab is recommended monthly. Depending on sample con-
ditions at individual locations and absence of input filters,
it may be necessary to clean the cell on a weekly basis.
This can be determined by observing the cell condition
when reagents are changed.
It is also highly recommended to clean the cell every time
you turn the meter off. In such a way, scaling and molds
growth are prevented. Otherwise, subsequent cleaning
might become more difficult.
For cleaning procedure, remove the plastic cap placed on
the top of the measuring cell.
Add a few drops of 19.2N Sulfuric Acid solution or alcohol
to the cell.
Allow sulfuric acid to stand in the measuring cell for 15
minutes to dissolve any foreign materials adhering to the
cell walls. Wipe the cell interior with a cotton-tipped swab.
After wiping, open the drain port to empty the measuring cell
from the cleaning solution.
