Contact Us

  Phone: (866) 650-1937
  Fax: (877) 880-1937

Follow Us

  Follow Us On Facebook  Follow Us On Twitter  Follow Us On LinkedIn  Follow Our Blog

Like Us on Facebook

Subscribe by Email to Blog

Your email:


Current Articles | RSS Feed RSS Feed

How to Monitor Desiccant Quality


Desiccant is a dehumidifying agent which attracts moisture from the atmosphere. It adsorbs and holds particles of water to itself.  When desiccant becomes soiled or broken down over time, it becomes less effective. Inadequate desiccant can increase energy consumption via lower compression efficiency, air leakage, or pressure variability.

Below are commons ways to monitor the quality of your desiccant using different methods of testing.

Indicating Color Change Silica Gel

Color Changing Silica GelIndicating Silica Gel is a silica gel bead or granule that has been washed with a concentration of cobalt chloride ( a heavy metal salt). The cobalt chloride is a deep blue color when it is dry and turns from blue to purple to pink as it becomes saturated with moisture. Typically, the color changes as the desiccant goes past 8% moisture levels (by weight) and indicates it is time to replace the desiccant.

The most typical use for an indicating silica gel is for a moisture sensitive product that will be inspected regularly as it gives a quick visual indication of how well it is doing. Because of the addition of cobalt chloride, indicating silica gel should not be used in contact with products for consumption such as food or pharmaceuticals.

Relative Humidity Indicator
Mositure Indicator

The Relative Humidity Indicator (RHI-01) is an economical way to test your compressed system for moisture. The indicating beads in the RHI-01 will start to change color at 10% RH and will be clear/pink at 15% RH. Indicating that you have damaging moisture in your system.

The RHI-01 will change hundreds of times before it needs to be replaced, so you can constantly monitor your air system.

Dew Point Monitors

Dew point is a fundamental unit and directly equivalent to water vapor pressure or parts per million. It is a very convenient measure of actual water content of a gas Dew Point Metersbecause it is not a function of temperature in the same way relative humidity is.

Knowing the compressed air dew point is critical to many processes. Excessive moisture can result in poor product quality, significant downtime, or corrosion and damage to critical equipment resulting in expensive repairs and lost revenue. To minimize moisture problems, reliable on-line dew point measurement is a must.

Self Testing Desiccant

Desiccant TestingBefore testing, observe the condition of the desiccant. If it looks discolored to a very dark brown or has chips and is turning to dust, these are visual signs of desiccant age. Visual inspection can also be a good indicator for when desiccant is required to be changed.

PDF Download: How to Test the Quality of Your Desiccant

eCompressedair Desiccant Testing

Typically, a bed of adsorbent desiccant lasts 3 to 5 years before needing replacement. eCompressedair can test the quality of your desiccant for you by sending in a sample of the used desiccant. We assure that the proper requirements and specifications are met during testing and return a report of the quality of desiccant.

Contact us today for more information on desiccant testing.

For more information, visit our website or contact our customer service team by calling toll-free: (866) 650-1937 or emailing