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It is also essential that the membrane is neatly trimmed off after fitting. If
"scraps" of loose excess membrane are left behind the "o" ring, these
can catch in the membrane protector thread as it is re-screwed, and pull
on the end of membrane, opening the seal.
How to check the membrane is fitted correctly...
Remove the plastic "Humidity" bottle from the end of the sensor. Rinse
the sensor tip in distilled water and wipe it dry with tissues etc. Hang the
sensor up overnight in a dry place.
If the membrane seal is leaking, white crystals of Potassium Chloride will
have formed under the edge of the membrane near the "o" ring, where
the electrolyte has leaked and crystallized. If these are visible, re-fit a
new membrane and re-test.
What will happen if the membrane is not fitted correctly ?
The Silver anode will usually turn black when it is poisoned. When the
anode is poisoned, the whole sensor is usually rendered unserviceable.
TPS may be able to re-furbish the sensor, but this is not certain.
1. Incorrect fitting of the membrane causes poisoning of the
sensor.
2. Poisoning of the anode is NOT covered by warranty.
Returning Sensors for Service
If the sensor has been used in wastewater where biological
contamination is likely, please clean the sensor before returning for
service.
Cleaning Instructions
Empty chambers, then thoroughly clean all matter from the sensor.
Decontaminate all exposed surfaces with 70% isopropyl alcohol, a fresh
solution of ¼ cup bleach to 5 litres of water or 5 % ammonia solution.