Checking The Ph Sensor - Polaris Watermatic C-660 User Manual

available and a sanitizer with a high pH such as calcium
hypochlorite or liquid chlorine (sodium hypochlorite) is used,
the ORP level may only rise to between 650 and 750 mV.)
4. If the sensor does not respond as indicated, the sensor
should be replaced.
C. Checking the pH Sensor
1. The pH sensor should be checked every six months or any-
time the pH goes out of range.
2. Place the sensor in a clean glass of tap water. Add a small
amount of acid to the glass. The pH reading should drop to
the lowest red light. Then place the sensor in any solution
with a pH above 7.5. The pH reading should move up.
3. If the sensor does not respond as indicated, the sensor
should be replaced.
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