Castair I7112VC2-S: 7.5 HP Single-Phase Industrial Air Compressor, 120-Gallon Vertical Tank
The Castair I7112VC2-S is a 7.5 horsepower, single-phase industrial-duty reciprocating air compressor built on a 120-gallon vertical ASME tank with a factory-mounted aftercooler. This is the largest single-phase tank option in the 7.5 HP Castair lineup, and it is designed specifically for shops that need extended run capacity without stepping up to a three-phase power requirement.
If your shop runs on standard 230-volt single-phase power and you find yourself waiting on the compressor to recover during busy production periods, the I7112VC2-S addresses that directly. The 120-gallon tank gives you 50% more stored air volume compared to the 80-gallon models in the same HP class — that means fewer compressor cycles per shift and more headroom for simultaneous air tool use.
Who This Compressor Is For
The I7112VC2-S fits shops that:
- Run on single-phase 230V power and cannot install three-phase service
- Have two or more technicians sharing an air system during peak hours
- Run air-hungry tools — plasma cutters, spray guns, large impact wrenches, tire inflation — that demand recovery headroom
- Want extended duty cycle without the cost of a duplex or rotary screw system
- Are stepping up from an 80-gallon unit and want more buffer before considering a three-phase compressor
Pump Design: Cast Iron, Slow RPM
Castair builds their industrial pumps from all cast iron — not cast aluminum. The difference matters in a production shop: cast iron handles heat better, wears more slowly, and is rebuildable when the time comes. This pump runs at 585 RPM, which is deliberate. Slow pump speeds reduce heat, reduce valve wear, reduce oil carryover, and dramatically extend pump life compared to the high-speed pumps found in consumer and prosumer compressors.
- All cast iron construction: Cylinder, head, crankcase — cast iron throughout for long service life
- Pump speed: 585 RPM — slow enough for quiet operation and reduced heat buildup
- Tapered roller bearings: Located at both ends of the crankshaft for superior support and reduced friction versus ball bearings
- Connecting rods: Precision steel rods with automotive-type insert bearings at the crankshaft and bronze bearings at the wrist pin — same design philosophy as industrial engine internals
- Disc and spring valves: Easier to service than reed valves, more efficient, and proven in industrial service
- 4-ring pistons: Four rings per piston for better compression efficiency and reduced oil blow-by compared to 2-ring designs
- Centrifugal unloader: The compressor starts unloaded every time — no cranking against full head pressure, which extends motor life significantly
Tank and Motor Specifications
- Tank capacity: 120 gallons, vertical orientation
- Tank construction: Powder-coated ASME-rated vertical tank with four legs for stable floor placement
- ASME safety valve: Factory installed
- Motor: 7.5 HP single-phase, 1725 RPM industrial motor with full 15% service factor or higher
- Voltage: 230V single-phase
- Belt guard: Metal, totally enclosed
- Discharge tube: Copper discharge and unloader tube, or stainless-steel braided flex line depending on configuration
Factory-Mounted Aftercooler (Included)
The -S suffix on this model means it ships with a factory-mounted beltguard aftercooler. An aftercooler cools the compressed air as it leaves the pump before it enters the tank, which causes moisture to condense and drop out before it reaches your lines and tools. For shops doing spray painting, sandblasting, or operating pneumatic controls, the aftercooler is not optional equipment — it is essential. Getting it factory-mounted saves installation time and ensures proper sizing for this pump.
Technical Specifications
- Model: I7112VC2-S
- Horsepower: 7.5 HP
- Phase: Single-phase (1-phase)
- Voltage: 230V
- Tank capacity: 120 gallons
- Tank type: Vertical (VC)
- Pump RPM: 585
- Free air delivery (CFM @ 0 PSI): 35.0 CFM
- Delivery at working pressure (CFM @ 175 PSI): 28.1 CFM
- Maximum working pressure: 175 PSI
- Dimensions (L x W x H): 44 x 30 x 75 inches
- Weight: 850 lbs
- Aftercooler: Factory-mounted beltguard aftercooler included
Available Configurations in the 7.5 HP Industrial Lineup
Castair offers the 7.5 HP industrial series in multiple tank sizes and configurations. Here is how the I7112VC2-S sits in the lineup:
- I718VC1-S — 7.5 HP, 1-phase, 80-gal vertical, 895 RPM, 32.4 CFM @ 0 PSI, 24.8 CFM @ 175 PSI, 32x24x74 in., 655 lbs — lighter pump, smaller tank, lower price point
- I718HC1-S — Same specs as VC1 but horizontal tank, 64x20x48 in., 655 lbs
- I718VC2-S — 7.5 HP, 1-phase, 80-gal vertical, 585 RPM, 35.0 CFM @ 0 PSI, 28.1 CFM @ 175 PSI, 40x24x74 in., 760 lbs — slower pump, same CFM but quieter
- I718HC2-S — Same specs as VC2 but horizontal tank, 64x20x46 in., 760 lbs
- I7112VC2-S (this unit) — 7.5 HP, 1-phase, 120-gal vertical, 585 RPM, 35.0 CFM @ 0 PSI, 28.1 CFM @ 175 PSI, 44x30x75 in., 850 lbs — maximum tank for single-phase
- I7312VC2-S — 7.5 HP, 3-phase, 120-gal vertical — same pump and CFM, but requires three-phase power; 820 lbs
When Does a Shop Need This vs. Stepping Up or Down?
Choose the I7112VC2-S if: You have single-phase power only, you are running two or more air tools simultaneously on a regular basis, or your current 80-gallon unit runs constantly during production and you need more buffer before stepping to three-phase or a rotary screw system.
Step down to an 80-gallon (I718VC2-S or I718HC2-S) if: You have limited floor space, your air demand is moderate (one technician, intermittent use), or budget is the primary constraint.
Step up to three-phase (I7312VC2-S or I7312HC2-S) if: You have three-phase power available and want a slightly lighter unit (820 vs 850 lbs) with the same output. Three-phase motors are generally more efficient and longer-lived at this HP rating.
Consider stepping up to 10 HP (I10112VC2-S) if: Your shop has heavy continuous demand — multiple spray booths, large lifts, or production-level tool use — and 28.1 CFM at 175 PSI is not enough headroom for your peak usage.
Factory Options Available at Time of Order
Castair offers several factory-mounted options for the industrial series. Options marked with an asterisk (*) are eligible for a 10% discount when ordered together as the All Options package (AOC2):
- Low Oil Control (#6304M): Shuts the compressor down if oil level drops too low — prevents pump damage from oil starvation
- Hour Meter (#HRM75M for 230V): Tracks runtime for scheduled maintenance intervals
- Air Operated Auto Drain (#ADVSM): Automatically drains condensate from the tank — critical for shop longevity in humid environments
- Electronic Auto Drain (#SDV03M): Timer-based electronic drain valve alternative to the air-operated version
- Dual Control (#DC2 for C2 pumps): Adds start/stop and constant speed control modes
- Intake Noise Silencers (#SA100x2M for C2 pumps): Reduces inlet noise significantly in enclosed shops
- Belt Tensioner (#215DM for 7.5 HP): Simplifies belt adjustment and maintains proper tension over time
- Time Delay 230V (#TD100M): Prevents rapid cycling from pressure switch chatter
- Vibration Pads (#VP1004): Set of four 4x4x1 inch pads to reduce floor vibration transmission
- Right from the Start Kit (#RFS002 for C2): Includes the essential startup accessories — belts, oil, filter, recommended by Castair for new installations
- Beltguard Aftercooler (#BGAC1M, 35 CFM rated): Already included on this -S model
Why Buy From Air Compressor Factory Direct?
We are a specialty compressor supplier, not a big-box retailer. When you call us, you talk to someone who knows the difference between a C1 and C2 pump, can tell you whether single-phase or three-phase makes sense for your shop, and can walk you through the option packages without upselling you on things you do not need. We carry the full Castair industrial lineup, ship direct from the distributor, and back every sale with manufacturer warranty support.
Free shipping on qualifying orders. Free tech support before and after the sale. Honest advice on whether this is the right unit for your application or whether you should be looking at a different HP or tank configuration.
Call 866-217-0063 for quick answers and help!
