Ofs Softcontrol Smart, Instruction Manual

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11.4. Malfunction/breakdown of the sensor
1. Deposits on the sensor
Precipitations and deposits on the sensor prevent appropriate hardness monitoring.
Examples:
Rust and iron deposits form a slightly red-brown layer in the flow measuring chamber and
on the sensor system

Upstream filters should prevent iron, copper or aluminum precipitation
Biofilm formation due to excessive germ counts in the water
Biofilms occur very strongly when the water softening system or the device has been
switched off for several days or weeks and the water is in the flow chamber.

If the device is not used for a longer period of time, it must be shut down electrically, the
sensor must be removed from the measuring chamber and stored accordingly, and the wa-
ter must be removed from the measuring chamber.
2. Chlorine exposure
Impact chlorination, as is sometimes carried out in raw water pipes, can damage the sensor
depending on its intensity and duration. Strong, deep black discolorations on the metal elec-
trodes indicate a high level of chlorine exposure. The sensor can indicate that the limit value
has been exceeded, although none is present.

The sensor is destroyed and must be replaced.
3. Brine exposure
Defective outlet valves on the softening system can cause brine from the brine tank to be
flushed into the soft water during regeneration, but also constantly when the water throughput
is weak, which could then be assessed as an excess hardness by the sensor system.
If the sodium concentration is very high compared to the calcium-magnesium concentration,
the sensor signal is strongly influenced by the excessive sodium content, as this has a disrup-
tive effect on the sensor. An increased brine concentration can be recognized by measuring
the conductance difference between raw and soft water. If the brine exposure is too high or
too intense, the sensor is destroyed, which means that a limit value alarm is displayed even if
the softening system is working correctly.

The sensor must be replaced.