Heatless Adsorption Dryers

The simplest and most common method used to regenerate the adsorbent desiccant material is the ‘heatless’ method (so called as it does not use heat for desiccant regeneration).

Using a proportion of the clean, dry process air for regeneration, heatless dryers typically have the lowest capital costs of all adsorption dryer types (due to the simplicity of the heatless design).

Being very robust and having fewer components, they typically have the lowest maintenance cost of all the adsorption technologies.

Heatless dryers are available to suit all compressed air flow rates from small to large, whereas the more complicated regeneration methods are often only available for higher flow rates due to cost and complexity of the designs.


  • Parker CDAS dryers provide a constant outlet dewpoint in accordance with ISO8573-1 classes 1, 2 or 3 for water vapour
  • Parker CDAS dryers provide an outlet dewpoint which inhibits the growth of micro-organisms (allowing their efficient reduction using filtration)
  • Parker CDAS dryers use clean, dry purge air for regeneration, eliminating any risk of damage to the adsorption bed or re-contamination of the downstream compressed air
  • Parker CDAS dryer performance has been tested in accordance with ISO7183, the international standard for compressed air dryer testing
  • The dewpoint performance of Parker CDAS dryers has been 3rd party validated by Lloyds Register to ISO8573-1 air purity classifications
  • No heat is used for regeneration; therefore, no insulation is required and loss of dewpoint on column changeover due to inefficient cool down is eliminated
  • Parker CDAS dryers include Parker OIL-X General Purpose & High Efficiency Coalescing pre-filtration and General Purpose Dry Particulate post filtration as standard
  • Full feature electronic control with dewpoint display and Energy Saving Technology fitted as standard

Compressed Air Treatment Redefined

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