Troubleshooting Guide - Apera Instruments PH20 Value User Manual

9.3. If you find white crystals inside or outside the probe cap, it is perfectly normal. It is the 3M KCL that
crystalizes over time by its nature. Just rinse them off and use the tester as normal. This chemical is not
poisonous nor dangerous, and the probe's performance will not be affected.
9.4. NEVER store the probe in pure water like tap, RO, distilled, or deionized water as they could damage the pH
probe. If this happens, immediately soak the pH probe Apera 3M KCL soak-ing solution overnight, then re-
calibrate it before using. Pure water is only for rinsing the probe.

10. Troubleshooting Guide

Trouble
Cannot calibrate
Reading is always slowly
changing, won't stabilize.
Display similar readings in
any solutions or always
display 7.0 pH
Reading keeps jumping
Calibration is successful, but
reading is not accurate
Reason
Pressing too soon
(showing
Poor quality standard solutions
(showing
Contaminated sensor
(showing
Incorrect calibration order
(showing
Broken probe
(showing
Dried-out probe
(showing
Probe is not fully submerged solution
(showing
Air bubbles around the sensor
(showing
Contaminated sensor
Clogged junction
Aged probe
Testing pH of low iconic strength
solutions like tap/drinking/RO/distilled
water
Broken probe
Instrument defect
Probe is not fully submerged in the
solution
Air bubbles around the sensor
Probe is not properly connected or the
pin connector is broken.
Aged probe
Air bubbles around the sensor
Clogged junction
Comparison with other testers, test
strips, or drop tests
Wait for
)
Replace with fresh and clean standard calibration solutions
) made by legitimate scientific instrument manufacturers.
Use a soft brush to clean the probe with Apera probe
) cleaning solution or detergent water.
Reboot tester, calibrate pH 7 first, then pH 4. For details
)
If you don't find any visible damage of the probe, contact
Apera for warranty fulfillment; If there is visible damage,
)
Soak the probe in Apera 3M KCL soaking solution for at
)
Make sure the probe is fully immersed in the solution at
)
Make a quick stir in the solution to remove air bubbles.
)
Use a soft brush to clean the probe with Apera probe
cleaning solution or detergent water.
Use a soft brush to clean the probe with Apera probe
cleaning solution or detergent water, then soak it in Apera
Be patient, wait for 1-5 minutes to reach a fully stabilized
reading. If still not stabilizing, add Apera 3M KCL solution
If you don't find any visible damage of the probe, contact
Apera for warranty fulfillment; If there is visible damage or
the probe is more than 6 months old, replace the tester.
Make sure the probe is fully immersed in the solution at
Make a quick stir in the solution to remove air bubbles.
Check the probe's connector, make sure it's not broken
and is correctly connected. Align the probe and instrument
correctly before plugging in. Never force it. Ensure that the
probe connector is not exposed in the air too long.
Make a quick stir in the solution to remove air bubbles.
Clean the probe with Apera probe cleaning solution, then
soak it in Apera 3M KCL soaking solution overnight
To compare with other testers, make sure to calibrate all
testers in the same pH 7 solution, then test pH 4.
Whichever gives more accurate reading is the more
accurate one. Test strips or drop tests' accuracy is not
How to fix
to stay on screen before pressing
refer to calibration notes (a)
replace the tester.
least 15 minutes.
least 1 inch deep.
3M KCL soaking solution overnight.
Replace the tester
to test water at 1:1000 ratio.
Contact us for warranty fulfillment
least 1 inch deep.
Replace the tester.
comparable to pH meters'.
5