ECD FCA-22 Instruction Manual page 21

Displayed value is Lower than
DPD test value (cont'd)
Zero Chlorine Reading
Unstable Chlorine Reading
Low tension on the
membrane
Flow to low through the flow
cell
Air bubbles trapped on
membrane
Air bubble inside the sensor
between cathode and
membrane
pH indication lower than
actual value
Temperature indication is
higher than actual value.
No electrolyte in the sensor
Open Circuit on FCS, broken
or bad electrical connection
Air bubbles on the membrane
Changing temperature, the
lag of the temperature sensor
looks like drift
Page 21
FCA‐22 Instruction Manual
Verify the Measuring
Chamber is fully tightened
onto the body or replace
membrane.
Clean CHFC, fittings and
tubing, verify the sample feed
rate at +10 gal/hr.
Loosen FCS fitting and lift
sensor slightly to purge air
trapped in the flow cell.
Refill sensor, see Maintenance
Calibrate pH sensor or adjust
value on uncompensated FCA
Calibrate the Temperature
(see Calibration) The
temperature sensor lags the
process temperature wait for
temperature equilibrium.
Refill Sensor
Check connector and wiring to
the connector inside the C‐22
Loosen FCS fitting and lift
sensor slightly to purge air
trapped in the flow cell.
Wait for equilibrium