Periodic cleaning of the CO2NTROL sensor may be required to remove process related build-up. This article explores best practices for cleaning inline and offline to ensure the best sensor performance.

Co2ntrol sensor

In-line Cleaning Considerations

In certain applications it may be desirable to clean the CO2NTROL sensor while installed within the vessel. The wetted components of the sensor are designed to withstand normal CIP (Clean-In-Place) chemicals such as NaOH, CLO2, and other chlorine-based disinfectants. The sensor is also resistant to common cleaning solvents such as ethanol, isopropyl alcohol, and acetone.

In-line Cleaning Best Practices

  • Avoid high pressure spray of cleaning solutions directly on the sensor wetted components. Devices like spray balls with high pressure water jet ( > 3 bar) could damage the sensing element and reduce sensor lifetime.
  • Cleaning chemicals and organic solvents may be aggressive; therefore prolonged exposure should be avoided. Expose the sensor to rinse water after the cleaning cycle to dilute or remove any residual cleaning chemicals.

Off-line Cleaning Considerations

After a run it may be necessary to remove the CO2NTROL sensor for cleaning. The cleaning procedure is described as follows:

  1. Remove sensor from the process
  2. Soak a dust-free cloth or tissue paper with deionized water and wipe the wetted parts with it. Thoroughly rinse the wetted parts and the sensor solid state sensing element with deionized water afterwards
  3. Dry the wetted parts with a clean dust-free cloth or tissue and store the sensor in dry conditions
  4. If the sensor’s sensing element is contaminated with oil, grease or other organic matter, soak a clean dust-free cloth with isopropyl alcohol. Rinse residual isopropyl alcohol immediately from the membrane with deionized water and gently wipe over the membrane surface
  5. After cleaning always perform a new two point calibration before carrying out measurements

Off-line Cleaning Video


Cleaning, assembly and maintenance should be performed by personnel trained in such work. Do not use any abrasive tissues or cleaning materials and do not use any cleaning chemicals other than described above. Before removing the sensor from the measuring setup, always make sure that the setup is pressure-less, cold and that no process medium can be accidentally spilled. When removing and cleaning the sensor, it is recommended to wear safety glasses and protective gloves.

Should CO2 Be a Critical Process Parameter?

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