The Castair ROFD6 is the OEM spin-on oil filter for Castair rotary screw compressors equipped with the D6 air end. The D6 air end is found in Castair's 15–20 HP rotary screw models — mid-range machines that deliver 52–80 CFM at 100 PSI in continuous-duty operation. The ROFD6 is a spin-on automotive-style filter, the same format Castair uses across their rotary screw line for ease of service without specialized tools or housing disassembly.
D6 Air End Applications
The D6 air end is used in Castair rotary screw models in the 15–20 HP class. These include machines in the R15 and R20 series equipped with the D6 (as opposed to G30) air end. If your model designation includes D6 or your service documentation references the D6 air end, this is the correct oil filter. If your 15–20 HP Castair uses a G30 air end instead, use the ROFD16-G30 filter.
Maintenance Context
- Filter type: Spin-on oil filter, automotive paper element design
- Maintenance kit: MKD6 — for D6 air end: 2 air filters (RAFD6-62), 4 oil filters (ROFD6), 1 separator filter (RSFD3-4-6-G11-P75), 5 gallons synthetic Cast-Lube oil — 10% savings vs. individual purchase
- Compatible oil: GA4000 or FG4000 Castair synthetic rotary screw lubricant (1 year/4,000 hour rating)
- Service interval: Replace with each scheduled oil change; track via the standard hour meter on all Castair rotary units
- Air filter for D6: RAFD6-62 — paper element, ID: 4-3/4", OD: 6-1/8", HGT: 2-7/8" (also fits D62)
Why Use OEM Filters
Castair designs their rotary screw compressors around off-the-shelf, serviceable components. The ROFD6 spin-on filter uses the correct bypass valve rating, correct thread specification, and correct media density for the D6 oil circuit. An aftermarket substitute with a different bypass rating can allow unfiltered oil circulation at low temperatures or under high-differential pressure conditions — exactly when you need filtration most. Use the OEM filter.
Technical Specifications
- Part Number: ROFD6
- Filter Type: Spin-on oil filter
- Compatible Air End: Castair D6
- Compatible Compressor HP: 15–20 HP rotary screw models
- Air Filter Cross-Reference: RAFD6-62 (shared with D62 air end)
- Manufacturer: Cast Air
Why Buy From OEM Diagnostic Tools?
Genuine Castair OEM filters shipped to your shop. Free shipping on qualifying orders. Free tech support at 866-217-0063. Full Castair manufacturer warranty. We can confirm the correct filter for your D6 compressor model.
Call 866-217-0063 for quick answers and help!
