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5.0 Maintenance
The sections below describe how to clean and replace the membrane cap
and electrolyte solution, and also how to store the sensor when not in use.
See section 4.0 Troubleshooting for assistance in determining when
maintenance may be required.
Cleaning the Membrane
Instructions for cleaning the membrane vary depending upon the type of
contamination. Follow the directions for replacing the membrane shown
below, replacing step 3 with one of these cleaning methods:
For general deposits:
Rinse in clear cold water.
For calcium scale:
Soak in dilute (1% by volume) hydrochloric acid, then rinse in clear cold
water.
For oils:
Rinse in isopropyl alcohol.
DO NOT use cleaners or detergents containing surfactants on the standard
free chlorine/bromine sensor membrane, as these will reduce the life of the
membrane.
If the sensor still cannot be calibrated after cleaning, replace the membrane
cap as described below.
Replacing the Membrane
CAUTION:
Wear gloves and safety glasses during assembly of
the sensor since the electrolyte is a STRONG ACID. It is
recommended to perform this operation over a sink with running
water available. After using, re-cap any remaining electrolyte until
the next use.
1.
Always move the gray band(s) to uncover the vent hole before
removing the membrane cap, or else the membrane will be
destroyed!
Hold the sensor vertically with the membrane facing down
and carefully unscrew the membrane cap.
2.
Rinse the electrolyte fill solution off the cap and electrodes with cold
water.
3.
Discard the old membrane cap.
4.
Unpack the new membrane cap, taking care not to touch the
membrane or get it dirty.
