CAUTION: There are live circuits inside the controller even when the power switch is in the
OFF position! Servicing and troubleshooting the controller must be performed by Qualified
Service Personnel.
1
W100/W600/W900 Controller
pH Electrode Troubleshooting Guide
Table of Contents
Section 1 Electrode Reading Responds Slowly
Section 2 Electrode Reading is Stuck on one Value
Section 3 Electrode Reads Low or High Versus a Calibrated Handheld Meter; Cannot Calibrate
Section 4 Electrode Fault
Section 5 pH Reading is Unstable
Note: pH electrodes are like batteries and their output voltage will change with time, even if they are not being
used. The useful life of a pH electrode is limited, and that time varies with the conditions it’s exposed to in the
application. Electrode life may be as short as one week in some aggressive applications (extreme temperature, pH
and/or pressure, dirty water, harsh chemicals) or more than a year in other applications with potable quality water at
room temperature.
