8
Reading is
always
slowly
changing,
won’t
stabilize
.
Contaminated
probe
Clean the probe with
Apera’s cleaning solution or
detergent water.
Clogged junction
Clean the probe with
Apera’s cleaning solution, then soak
it in 3M KCL soaking solution overnight.
Aged probe
Replace the probe.
Testing pH of low
iconic strength
solutions like tap
water, drinking
water, RO water
Be patient, wait for 2-5 minutes to reach a fully stabilized
reading. If still not stabilizing, add 1ml of 3M KCL solution
to 1000ml of test solution.
Display
similar
readings in
any
solutions or
always
display 7.0
Broken probe
If you
don’t find any visible damage of the probe and it’s
within the 1-year probe warranty, contact your point of
purchase for warranty fulfillment;
If there is visible damage
or the probe is more than 1-year old, replace the probe.
Reading
keeps
jumping
Probe is not fully
submerged in the
solution
Make sure the probe is fully immersed in the solution at
least 1 inch deep.
Air bubbles
around the sensor
Make a quick stir in the solution to remove air bubbles.
Probe is not
properly
connected, or the
pin connector is
broken.
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.
Calibration
is
successful,
but reading
is not
accurate
Aged probe
Replace the probe.
Air bubbles
around the sensor
Make a quick stir in the solution to remove air bubbles.
Clogged junction
Clean the probe with cleaning solution, then soak it in 3M
KCL soaking solution overnight
Comparison with
other testers, test
strips, or drop
tests
To compare with other testers, make sure to perform a 2-
point calibration for all testers in the same standards, then
test a 3rd point. Whichever gives more accurate reading
in the 3rd point standard is the most accurate one.
Test
strips or drop
tests’ accuracy is not comparable to pH
meters’.
Out of range reminder for pH
Out of range reminder for temperature
