The Castair 10-215-1 is a 10 HP single-phase open drip proof motor built specifically for industrial air compressor service. This is a replacement motor for Castair industrial and commercial compressor systems that run on 208/230V single-phase power. If you are rebuilding a Castair industrial compressor or replacing a failed motor on an existing unit, this is the correct OEM replacement for 10 HP single-phase applications.
Motor Specifications
- Horsepower: 10 HP
- Phase: 1-Phase
- Voltage: 208/230V
- Service Factor: 1.25
- Amp Draw: 46A at 208V / 43A at 230V
- Frame: 215T NEMA frame
- RPM: 1725
- Shaft Size: 1-3/8 inch
- Weight: 165 lbs
- Listings: UL and CSA listed
- Enclosure: Open Drip Proof (ODP)
- Part Number: 10-215-1
Why 1725 RPM Matters for Compressors
Most single-phase motors run at 3450 RPM. The 10-215-1 runs at 1725 RPM — half speed. That is intentional. Castair industrial compressors are designed around slow-speed pump operation, which means less heat, less wear, and a quieter system. A 1725 RPM motor paired with properly sized pulleys keeps the pump running at the correct RPM for maximum efficiency and service life. If you are replacing this motor, do not substitute a 3450 RPM motor — it will over-speed the pump and void the warranty.
Frame and Shaft Compatibility
- 215T frame: Standard NEMA T-frame — fits the existing motor mount on Castair industrial units designed for 10 HP single-phase
- 1-3/8 inch shaft: Matches Castair P2B-series pulleys (6.25", 6.75", 8.0", 8.75" OD options with 1-3/8" fixed bore)
- 165 lbs weight: Confirm your motor base can handle this — for 7.5-10 HP applications, Castair uses the 213D or 215D adjustable belt tensioner base
Open Drip Proof Enclosure
Open drip proof (ODP) motors have ventilation openings that allow air to circulate through the motor for cooling. They prevent liquid from dripping into the motor at angles up to 15 degrees from vertical. This makes them suitable for indoor installations in clean, dry environments — typical for most shop compressor rooms. They are not rated for outdoor use or washdown environments. If your compressor room is particularly dusty, ask about totally enclosed options.
Single-Phase vs. Three-Phase: Which Do You Need?
- Single-phase 10-215-1 ($1,416.80): Required when three-phase power is not available. Draws 46A at 208V or 43A at 230V — confirm your service panel and wire gauge are rated for this load.
- Three-phase 10-215-3 ($993.53): If you have three-phase power, this is the better motor — lower cost, lower amp draw (30/28/14A across all three voltages), and typically longer service life in continuous duty. Same frame and RPM.
The choice is driven by what power is available at your facility. You cannot use the single-phase motor on a three-phase circuit or vice versa.
What's in the Box
- 1x Castair 10 HP open drip proof motor, 208/230V 1-phase, Frame 215T, 1725 RPM
- Standard motor leads and terminal connections
Note: Pulleys, belts, and motor base sold separately. For 7.5-10 HP installations, see Castair part numbers 213D/213DM or 215D/215DM (adjustable belt tensioner bases), and P2B-series pulleys for 1-3/8 inch shafts.
When Does a Shop Need This vs. Stepping Up or Down
You need the 10-215-1 when you are replacing a failed 10 HP single-phase motor on an existing Castair industrial compressor, or building a new 10 HP single-phase system. The 165 lb motor weight and 215T frame are specific to this HP class — the smaller 7.5 HP single-phase motor (7-215-1) uses the same 215T frame but a lighter weight and lower service factor. Do not upsize to this motor if your system was designed for 7.5 HP; the pulleys and belt sizing are calculated for the rated HP. If you are unsure what motor your unit originally had, the part number is stamped on the motor nameplate — call us and we'll look it up.
Why Buy From Air Compressor Factory Direct?
We have been specializing in industrial air compressor components since 2016. We stock Castair motors, pumps, tanks, and accessories — not just complete units. When your compressor is down, you need the correct replacement part fast, with someone who can confirm fitment before you order. Free shipping on every order, free technical support at 866-217-0063, and full manufacturer warranty on all Castair components we sell.
Call 866-217-0063 for quick answers and help!
