Castair Refrigerated Dryer Replacement Filter Element — .016 Micron (RD.016-S)
The Castair RD.016-S is a .016 micron replacement filter element for use with refrigerated compressed air dryer pre-filter assemblies. Pre-filtration is required by Castair before all refrigerated dryers — the manufacturer specifies a properly sized pre-filter as a condition of warranty coverage. The RD.016-S element fits the S-series filter housing in the Castair dryer pre-filter lineup. The .016 micron rating provides fine coalescing filtration, capturing oil aerosols and fine water droplets that a standard 5-micron particulate filter passes.
Specific housing dimensions, housing compatibility, and replacement interval specifications for the RD.016-S were not published on castair.net at time of writing. Call 866-217-0063 with your dryer model and line size to confirm this is the correct replacement element for your installation.
Filter Specifications
- Part number: RD.016-S
- Filtration rating: .016 micron
- Filter type: Coalescing replacement element (S-series housing)
- Application: Pre-filter for Castair refrigerated compressed air dryers
- Housing compatibility: S-series filter housing — contact 866-217-0063 to confirm your housing
Why Micron Rating Matters Before a Refrigerated Dryer
A refrigerated dryer works by cooling compressed air to condense water vapor. Oil mist in the compressed air coats the heat exchanger surfaces over time, reducing heat transfer efficiency and degrading dew point performance. A coalescing pre-filter upstream of the dryer removes oil aerosols before they reach the heat exchanger, extending dryer service life and maintaining consistent dew point performance. The .016 micron RD.016-S provides finer filtration than a standard 5-micron particulate filter — appropriate for systems with higher oil carryover from the compressor.
Filter Series Comparison (Castair)
- RD.016-S (this part): .016 micron coalescing — finest filtration in the RD series
- RD.030-S: .030 micron coalescing — intermediate filtration
- RD.060-S: .060 micron coalescing — coarser pre-filtration
For context, Castair's C-CF series coalescing filters are rated at .01 micron and are used in final point-of-use filtration after the dryer for the most critical applications (spray painting, pneumatic instruments). The RD-series elements are pre-dryer coalescing protection.
When to Replace
- Follow the differential pressure indicator on your filter housing — replace when the indicator shows the element is loaded
- In high-oil-carryover situations (older compressors, poorly maintained separators), coalescing elements load faster — inspect more frequently
- A loaded coalescing filter will pass oil mist to the dryer, coating the heat exchanger and reducing dew point performance
What Is in the Box
- 1x Castair RD.016-S replacement filter element, .016 micron
Why Buy From Air Compressor Factory Direct?
- Castair authorized: OEM replacement element
- Free shipping on qualifying orders
- Free tech support: 866-217-0063 — confirm element compatibility with your housing and verify correct micron rating for your application
- Full dryer accessory lineup: Pre-filters, elements, housings, bypass valves, and installation kits
Call 866-217-0063 for quick answers and help!
