Myron L 6P (includes Addendum 10-01) User Manual
Page 16

XII.
TROUBLESHOOTING CHART
27
Symptom
Possible Cause
Corrective Action
No
display
, even though
Battery weak or not connected.
Check connections or replace battery
measurement key pressed
(ref. Battery Replacement, pg. 24).
Inaccurate
pH
readings
1. pH calibration needed (ref. pH Cal., pg. 17). 1. Recalibrate instrument.
2. Cross-contamination from residual pH
2. Thoroughly rinse sensor well.
buffers or samples in sensor well.
3
. Recalibrate using fresh buffers (ref. pH
3. Calibration with expired pH buffers.
Buffer Solutions, pg. 28).
No response to
pH
changes
Sensor bulb is cracked or an
Replace pH/ORP sensor (ref. pH/ORP
electromechanical short caused by an
Sensor Replacement, pg. 29).
internal crack.
Will not adjust down to
pH
7
pH/ORP sensor has lost KCl.
Clean and rejuvenate sensor (ref. Cleaning
Sensors, pg. 25) and recalibrate. If no
improvement, replace pH/ORP sensor
(ref. pH/ORP Sensor Replacement, pg. 29).
pH
readings drift or respond
1. Temporary condition due to “memory” Clean and rejuvenate sensor (ref. Cleaning
slowly to changes in
of solution in pH sensor well for long
Sensors, pg. 25) and recalibrate. If no
buffers/samples or “FAC” is
periods.
improvement, replace pH/ORP sensor
displayed repeatedly
2. Bulb dirty or dried out.
(ref. pH/ORP Sensor Replacement, pg. 29).
3. Reference junction clogged or coated.
Unstable
1. Dirty electrodes.
1. Clean cell cup and electrodes (ref.
Conductivity
/
T D S
/
2. Test samples greater than 1 megohm.
Cleaning Sensors, pg. 25).
Resistivity
readings
2. Minimize test sample exposure to air
(ref. Measuring Resistivity, pg. 10).
Unable to calibrate
Film or deposits on electrodes.
Clean cell cup and electrodes (ref.
Conductivity
/
T D S
Cleaning Sensors, pg. 25).
Resistivity
readings much
1. Contamination from previous sample or 1. Rinse cell cup more thoroughly before
lower than expected
from pH sensor well.
measurement. Ensure pH cap is snugly
2. Carbon dioxide in test sample.
in place.
2. See Measuring Resistivity, pg. 10.