Myron L TH1 - Manual (Page 26)

22
Symptom
No display, even
though measurement
key pressed
Inaccurate pH readings
(TPH1)
No response to
pH changes (TPH1)
Will not adjust down
to pH 7 (TPH1)
pH readings drift or
respond slowly to
changes in buffers/
samples (TPH1)
or
“FAC” is displayed
repeatedly (TPH1)
Unstable
Conductivity/TDS
readings
Unable to calibrate
Conductivity/TDS
Possible Cause
Battery weak or not connected
1. pH calibration needed (ref. pH Cal, pg. 12).
2. Cross-contamination from residual pH
buffers or samples in sensor well.
3. Calibration with expired pH buffers.
Sensor bulb is cracked or there is an
electromechanical short caused by an
internal crack.
pH sensor has lost KCl.
1. Temporary condition due to “memory”
of solution in pH sensor well for long
periods
2. Bulb dirty or dried out
3. Reference junction is clogged or coated.
Dirty electrodes
Film or deposits on electrodes
XV. TROUBLESHOOTING CHART