28
Conductivity Sensor
• The conductivity sensor should be cleaned periodically. The frequency of cleaning will
vary by installation.
• To determine how often the probe must be cleaned, follow the procedure below:
– Read and record the conductivity.
– Remove, clean and replace the conductivity probe.
– Read conductivity and compare with the initial reading.
– If the variance in readings is greater than 5%, increase the frequency of probe
cleaning. If there is less than a 1% change in the reading, the probe can be cleaned
less often.
– An accumulation of scale, dirt, or debris on the sensor can impact the accuracy of
the sensor. Thus the probe must be cleaned periodically. This can be accomplished
by scrubbing with a toothbrush or other stiff brush. Depending on the impurity,
various cleaners can be used to help. Detergent or isopropyl alcohol cleaner may
help remove oils. A mild acid, such as white vinegar, will help to remove calcium
scale. A fine grit abrasive cloth can also be used to remove scale, though harsh
abrasives should be avoided. Rinse the sensor thoroughly before returning to service.
– The conductivity controlled bleed system of the Nexus
®
Modular Hybrid Cooler will
automatically maintain the desired cycles of concentration in the recirculating water
system. Refer to Bleed Rate on
page 36
for more details.
Figure 30.
Conductivity Sensor
Figure 31.
High and Low Level Switches
High Level and Low Level Switches
Water level switches are constructed of stainless steel, which is well-suited for corrosive
environments. Perform routine maintenance every six months (at start-up and shutdown) to
avoid any scale build up on the stem. Ensure the floats can travel freely along the stems.
NOTE:
BAC recommends adjusting
the conductivity setpoint in the
iPilot
®
Control System to best
minimize water consumption and
keep heat transfer surfaces scale-
free.