NDL Heatless Modular Desiccant Air Dryer With Integrated After Filter By Nano

Who needs the nano NDL

A refrigerated dryer gets compressed air to about a 38 F dew point. That is dry enough for most shops, but not for air lines that run outdoors or through unheated space in winter, for powder coating and critical paint, for laser and plasma cutting, for instrumentation and controls, or for food, pharmaceutical and lab work that specifies ISO 8573-1 Class 2 water. The nano NDL is a heatless regenerative desiccant dryer that delivers a minus 40 F pressure dew point as standard, or minus 94 F in the GF2 LDP versions, from 2 to 1110 CFM. Two desiccant towers alternate: one dries the air while a slip stream of dry air purges the other, controlled by a PLC with run hour tracking and service indicators.

Sizing it

Size the NDL on the full output of the compressor at the dryer inlet pressure, not on the tools downstream. Ratings are at 100 PSIG inlet and 100 F inlet air; capacity rises with inlet pressure and falls with lower pressure or hotter air. A 25 HP screw making about 100 CFM wants an NDL 110 (106 CFM) or NDL 120 (132 CFM) for margin. Remember that a heatless dryer uses roughly 15 percent of its rated flow as purge air, so the compressor must have that much spare capacity; the optional energy saving dew point control cuts purge when demand is low. The low dew point versions carry a lower CFM rating on the same frame, so step up a size when you move to GF2 LDP.

Installation and what comes with it

Every NDL ships with a 1 micron after filter built in and a 0.01 micron GFN coalescing prefilter packed loose. Install the prefilter immediately upstream with a drain; oil and bulk water are what kill desiccant. Mount the dryer after the receiver and, on larger systems, downstream of a refrigerated dryer so the desiccant handles only the last stage of drying. The universal 85 to 264 VAC supply runs on any shop circuit. Working pressure is 58 to 232 PSIG on the NDL 010 through 130 and 145 PSIG standard on the larger frames, with a 232 option. Connections run from 3/8 inch NPT to 2-1/2 inch NPT by model.

Meeting an ISO 8573-1 air quality spec

If your spec calls out an ISO 8573-1 class, here is how the NDL lines up. Water: the standard -40°F pressure dew point meets Class 2 and any spec written at -7°C, 20°F or 35°F. Particles: the built-in 1.0 micron after filter meets a 1 micron limit; add a 0.01 micron filter downstream for Class 1. Oil: the included 0.01 micron coalescing prefilter brings oil aerosol to 0.01 mg/m³. Because ISO oil classes count vapor too, a Class 1 oil spec on a lubricated compressor needs an activated carbon filter after the dryer, or an oil-free compressor. The optional dew point control gives a live readout for monthly checks, but ISO 8573-2, -3 and -4 compliance testing is done by sampling, not by the dryer. Note that ratings are at 100 PSIG: at 80 PSIG an NDL 020 delivers about 4 CFM, so for 4 to 5 CFM pick the NDL 030.

Related pages

See the whole nano desiccant dryer family and the nano brand page, replacement elements on the nano filters page, and all desiccant air dryers. Comparable heatless units are the Atlas Copco CD and the Quincy QCMD; for a 38 F dew point at lower cost see the refrigerated air dryers.

nano NDL Heatless Modular Desiccant Air Dryer

Heatless regenerative modular desiccant dryers from nano-purification solutions, 2 to 1110 SCFM, delivering ISO 8573-1:2010 Class 2 water (-40°F pressure dew point) and Class 2 dirt (1 micron) as standard. Every GF unit includes a built-in 1.0 micron after filter plus a 0.01 micron GFN coalescing pre-filter shipped loose. Low Dew Point (GF2 LDP) versions deliver -94°F pressure dew point.

Key Specifications

• Maximum working pressure: 232 psig (MAWP) as standard on models NDL 010 through NDL 130. Models NDL 2110 through NDL 6130 are rated 145 psig as standard, with a 232 psig option available.
• Minimum working pressure: 58 psig
• Pressure dew point: -40°F standard (GF), -94°F low dew point (GF2 LDP)
• Flow ratings: at 100 psig inlet, 100°F inlet air; capacity increases with inlet pressure
• Inlet air temperature: 35 to 100°F recommended, 122°F design maximum
• Electrical supply: 85 to 264 VAC, 50/60 Hz universal
• Control: PLC with run-hour tracking and service indicators; Energy Saving Dew Point Control (purge saving) available as an option
• Filtration: integrated 1.0 micron after filter, 0.01 micron coalescing pre-filter shipped loose

Models, part numbers and configurations

All variants and part numbers for this product are listed below for easy reference and ordering.