Dew point sensor life depends on:

Air temperature and flow passing over the sensor.

The amount of fines (dust) in the process air.

The amount of plasticizer vapor in the process air.

Once every six months, the dryer operator should monitor the initial dew point sensor readings and establish a periodic replacement schedule as needed.

Caution! Do not attempt to check the continuity or resistance of the dew point sensor.

The sensor will be destroyed!

5-3 Corrective Maintenance

This section provides you with the information necessary to correct or repair any issues which might appear during the normal operation of your dehumidifying dryer. Although we have listed how to perform these procedures, it is recommended that you call the Service Department to have any in-depth maintenance performed.

Symptoms of Worn Desiccant

The moisture absorption capacity of the desiccant used in your dehumidifying dryer degrades after an indefinite period of time. Useful life depends on variables such as material moisture content, plasticizer vapors in the return air, and number of regeneration cycles.

Your dryer may need new desiccant if it exhibits any of the following symptoms:

The process air dew point measured with a portable dew point monitor is higher than -10°F (-23ºC) throughout the process drying cycle.

Noticeable amounts of desiccant in the beds is a medium-brown color or darker.

If you notice any of these signs, replace the desiccant in the desiccant beds. Desiccant replacement kits are available from the Parts Department. If you want, a technician can repack desiccant beds at your site.

Dehumidifying Dryers

Chapter 5: Maintenance

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Sterling SDAA 25-100 specifications Corrective Maintenance, Symptoms of Worn Desiccant