Refrigerated Air Dryers

Refrigerated air dryers are the workhorse choice for treating plant compressed air. They cool the incoming compressed air in a heat exchanger so water vapor condenses into liquid, which is removed by a drain separator and discharged automatically through an auto drain. The dried air is then reheated before it leaves the dryer. The result is reliable, continuous moisture removal at a pressure dew point down to roughly 37°F (3°C) — dry enough for the large majority of industrial pneumatic applications. Automation Distribution stocks the full SMC refrigerated air dryer range: IDF, IDFA, IDFB, IDU, and IDH series.

Why choose a refrigerated air dryer?

For general industrial compressed air — powering pneumatic tools, cylinders, valves, and actuators — a refrigerated dryer is almost always the primary dryer on the system. It delivers the moisture protection most plants need at a lower running cost than desiccant drying, with simple controls and easy servicing. SMC refrigerated dryers use environmentally friendly R134a or R407C refrigerants with zero ozone-depletion potential, and many models feature stainless steel plate-type heat exchangers for improved corrosion resistance. Removing moisture protects against rust in piping, dripping grease and malfunction in valves and actuators, and degradation of downstream auto drains.

Which SMC refrigerated dryer series do I need?

SMC's refrigerated dryer series differ mainly by regional certification, inlet air temperature range, and flow capacity. Match the series to where the dryer will be installed and the conditions it will see:

  • IDFB Series — standard inlet air temperature dryers cUL listed for use in North America. 60 Hz models with rated flows up to 459 scfm, suited to aftercooled systems with compressors up to roughly 100 hp. The default choice for most U.S. installations.
  • IDF Series — standard inlet air temperature dryers for 50 or 60 Hz operation worldwide where specific regional certifications aren't required. This series includes SMC's largest units, with rated flows up to 2,295 scfm.
  • IDFA Series — CE marked standard inlet air temperature dryers for use in Europe and other regions requiring the CE mark. 50 Hz models with rated flows up to 883 scfm. See also the IDFA*E sizes for the larger-capacity variants.
  • IDU Series — high inlet air temperature dryers for inlet air up to 176°F (80°C). Designed for use with compressors or systems that don't include an aftercooler, the IDU's integral aftercooler and stainless steel heat exchanger deliver a stable supply of dry air under high-demand conditions. Well suited to reciprocating compressors.
  • IDH Series — a compact air dryer with outlet air temperature adjustment, integrating a heater, regulator, dryer, and filter. The IDH delivers a constant volume of compressed air at a controlled temperature, dew point, pressure, and cleanliness regardless of seasonal or ambient conditions — ideal for air bearings and other applications needing constant, controlled-temperature dry air.

Refrigerated vs. desiccant vs. membrane

A refrigerated dryer reaches a pressure dew point around 37°F — sufficient for most general industrial use and the standard primary dryer for plant air. If your application needs a much lower dew point (instrumentation, sub-freezing air lines, ISO 8573-1 Class 3 or better), see desiccant air dryers. For compact, power-free drying at a single machine, see membrane air dryers. The full air dryer range covers all three technologies.

Don't forget upstream filtration and accessories

A refrigerated dryer performs best with bulk water, oil, and particulate removed ahead of it. SMC recommends an AFF main line filter as a pre-filter to prevent fouling of the dryer's heat exchanger — browse main line filters, water separators, and aftercoolers to complete the air treatment train. For replacement parts and installation hardware, see dryer accessories.

Buy SMC refrigerated air dryers from Automation Distribution

Automation Distribution is an authorized SMC distributor. Browse the SMC IDF, IDFA, IDFB, IDU, and IDH refrigerated air dryers below, or contact our team for help sizing a dryer to your compressor capacity, flow rate, inlet air temperature, and required pressure dew point.