Castair 5 HP Industrial Two-Stage Cast Iron Air Compressor — 17.5 CFM @ 175 PSI, 80 Gal ASME Tank
The Castair 5 HP Industrial Air Compressor is a heavy-duty, two-stage cast iron piston compressor engineered for the demands of a working shop. It delivers 22 CFM at 0 PSI and 17.5 CFM at 175 PSI, driven by an oversized cast iron pump that runs at a deliberately slow RPM for quiet operation and long service life. The whole unit comes self-contained on a powder-coated ASME-certified tank with heavy-duty industrial controls. Built to order by Castair, a family-owned Minnesota manufacturer since 1991.
Why It's Different: Castair builds these pumps to last: all cast iron construction, tapered roller bearings at both ends of the crankshaft, precision steel connecting rods with automotive-type insert bearings, disc-and-spring valves for easy service and higher efficiency, and four-ring pistons that cut oil carry-over. A centrifugal unloader gives a load-less start-up every time. The slow-RPM design is the key difference from cheaper high-speed compressors — it runs cooler and quieter and lasts dramatically longer under daily shop use.
Best For: Small shops and dedicated tool circuits that need durable, quiet continuous shop air.
Configuration: Choose single-phase or three-phase power, a 80-gallon ASME tank, vertical or horizontal tank orientation, and your choice of pump build (a faster standard build or a slower-RPM build that runs quieter and, on some models, moves more air).
⚠️ BEFORE YOU ORDER — PLEASE READ: This is a heavy-duty, built-to-order industrial compressor.
• Electrical: requires a dedicated 208–230V circuit (single-phase or three-phase, per your selected model), installed by a licensed electrician with proper grounding.
• Lead time: all Castair units are built to order — confirm current production lead time before purchase.
• Weight & placement: 590–700 lb depending on configuration; requires a level floor rated for the load, adequate ventilation for heat dissipation, and freight handling for delivery.
It is the customer's responsibility to verify electrical service, floor space, and ventilation before purchase and installation.
Features
-
Two-stage oversized cast iron pump built for long life and quiet operation
-
17.5 CFM @ 175 PSI rated output (22 CFM @ 0 PSI | 17.5 CFM @ 175 PSI)
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Slow-RPM design (420–995 RPM range across the series) for cooler, quieter, longer-lasting operation
-
Tapered roller bearings at both ends of the crankshaft
-
Precision steel connecting rods with automotive-type insert bearings
-
Disc & spring valves for easy service, higher efficiency & reliability
-
Four-ring pistons for higher efficiency and less oil carry-over
-
Centrifugal unloader for a load-less start-up every time
-
Powder-coated ASME-certified tank with ASME safety valves
- Totally enclosed metal belt guard
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Copper discharge & unloader tube or stainless-steel braided flex line
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Heavy-duty 1,725 RPM industrial motor with full 15% service factor or higher
Specifications
| Castair Industrial 5 HP — 22 CFM @ 0 PSI | 17.5 CFM @ 175 PSI |
| Model |
Phase |
Tank (Gal) |
Orientation |
Pump RPM |
CFM @ 175 PSI |
L × W × H (in) |
Wt (lb) |
| I518VC1-S |
Single |
80 |
Vertical |
767 |
17.5 |
32×24×74 |
600 |
| I518HC1-S |
Single |
80 |
Horizontal |
767 |
17.5 |
64×20×48 |
600 |
| I518VC2-S |
Single |
80 |
Vertical |
420 |
17.5 |
40×24×74 |
700 |
| I518HC2-S |
Single |
80 |
Horizontal |
420 |
17.5 |
64×20×46 |
700 |
| I538VC1-S |
Three |
80 |
Vertical |
767 |
17.5 |
32×24×74 |
590 |
| I538HC1-S |
Three |
80 |
Horizontal |
767 |
17.5 |
64×20×48 |
590 |
| I538VC2-S |
Three |
80 |
Vertical |
420 |
17.5 |
40×24×74 |
690 |
| I538HC2-S |
Three |
80 |
Horizontal |
420 |
17.5 |
64×20×46 |
690 |
| Shared Specifications |
| Manufacturer |
Castair (Spicer, Minnesota — family-owned since 1991) |
| Type |
Two-stage cast iron piston air compressor (industrial), ASME tank |
| Total HP |
5 HP |
| Output |
22 CFM @ 0 PSI | 17.5 CFM @ 175 PSI |
| Pump |
Two-stage, oversized cast iron, slow-RPM, 4-ring pistons |
| Motor |
Heavy-duty 1,725 RPM industrial, 15% service factor or higher |
| Voltage |
208–230V, single-phase or three-phase |
| Tank |
80 gal, powder-coated ASME-certified, vertical or horizontal |
| Certification |
ASME-certified air receiver tank & ASME safety valves |
| Brand |
Castair |
What's Included
- Two-stage cast iron compressor self-contained on a powder-coated ASME tank
- Heavy-duty 1,725 RPM industrial motor
- Totally enclosed metal belt guard
- Copper discharge & unloader tube (or stainless braided flex line)
- ASME safety valves, centrifugal unloader
- (Factory-mounted options available — low oil control, hour meter, auto tank drain, dual control, intake silencers, belt tensioner, vibration pads, beltguard aftercooler, Right-From-the-Start kit. Order all asterisk options together for 10% off. Contact us to configure.)
Manuals & Documentation