{"product_id":"castair-7hp-3-phase-industrial-air-compressor-horizontal-tank-w-mounted-starter-i733hc2-s","title":"Castair 7HP 3-Phase Industrial Air Compressor  Horizontal Tank w\/ Mounted Starter - I733HC2-S","description":"\u003cp\u003eThe Castair I733HC2-S is a 7.5 HP, 3-phase industrial air compressor on a 30-gallon horizontal ASME tank, equipped with the larger C2 pump and a factory-mounted magnetic motor starter. Where the I733HC1-S runs the C1 pump at 895 RPM and delivers 24.8 CFM at 175 PSI, the I733HC2-S steps up to the C2 pump running at 585 RPM — producing 35.0 CFM at 0 PSI and 28.1 CFM at 175 PSI. That extra CFM capacity is the main reason to choose the C2 variant over the C1, especially if your shop has higher sustained air demand but still wants the compact 30-gallon horizontal tank footprint.\u003c\/p\u003e\n\n\u003cp\u003eThe C2 pump is a two-stage, four-cylinder V4 cast iron unit. It runs slower than the C1 (585 vs. 895 RPM), which keeps operating temperatures lower and extends pump life further. Both pumps are all cast iron — no aluminum pump heads to warp under heat — and both are belt-driven from the 1,725 RPM industrial motor down to their rated pump speed.\u003c\/p\u003e\n\n\u003ch2\u003eC1 vs. C2 Pump — Which One Do You Actually Need?\u003c\/h2\u003e\n\u003cp\u003eThis is the key decision in the I733 lineup. Here's how to think about it:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eC1 pump (I733HC1-S):\u003c\/strong\u003e 895 RPM, 24.8 CFM@175PSI — handles two to three air tools simultaneously, good for general shop work: impacts, ratchets, blow guns, tire inflators\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eC2 pump (I733HC2-S, this unit):\u003c\/strong\u003e 585 RPM, 28.1 CFM@175PSI — adds about 3.3 CFM at working pressure, which matters when you're running heavier tools like DA sanders, air chisels, or a spray gun alongside other tools\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSlower RPM of the C2:\u003c\/strong\u003e 585 vs. 895 RPM means the C2 runs even cooler and quieter than the C1 — the tradeoff for the larger pump is a heavier unit\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003ePump Features — Cast Iron C2 Two-Stage V4\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eAll cast iron V4 cylinder configuration:\u003c\/strong\u003e Four cylinders in a V arrangement — more displacement per revolution than the C1 inline-2, producing higher CFM at lower RPM\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSlow 585 RPM operation:\u003c\/strong\u003e Even cooler and quieter than the C1 due to the lower shaft speed and larger flywheel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTapered roller bearings at both crankshaft ends:\u003c\/strong\u003e Superior support under belt-drive side loads and sustained two-stage compression\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePrecision steel connecting rods:\u003c\/strong\u003e Automotive-type insert bearings at crankshaft, needle bearings at wrist pin\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDisc and spring valves:\u003c\/strong\u003e Easy to service, reliable under continuous duty cycling\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e4-ring pistons:\u003c\/strong\u003e Reduced oil carry-over into the discharge air stream\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCentrifugal unloader:\u003c\/strong\u003e No-load start on every cycle — protects motor and pump from high-inertia starts under pressure\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eTank and Frame Features\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e30-gallon horizontal ASME-rated tank:\u003c\/strong\u003e Powder coated, channel-supported — same footprint as the HC1 variant\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eASME safety valve:\u003c\/strong\u003e Factory installed and rated for working pressure\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMetal belt guard:\u003c\/strong\u003e Fully enclosed, OSHA-compliant\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCopper discharge and unloader tube:\u003c\/strong\u003e Better heat dissipation than rubber or plastic lines\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eMotor and Electrical\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e1,725 RPM heavy-duty industrial motor:\u003c\/strong\u003e Full 15% service factor — continuous duty rated\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFactory-mounted magnetic motor starter:\u003c\/strong\u003e 3-phase overload protection, wired at the factory — ready to connect to your electrical service\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e3-phase operation:\u003c\/strong\u003e Smooth starts, lower peak current draw, longer motor life than single-phase equivalents\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eWhat's in the Box\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eCastair I733HC2-S compressor assembly (C2 pump, motor, 30-gal horizontal tank, belt drive, belt guard)\u003c\/li\u003e\n\u003cli\u003eFactory-mounted magnetic motor starter (3-phase, sized for 7.5HP)\u003c\/li\u003e\n\u003cli\u003eASME safety valve (installed)\u003c\/li\u003e\n\u003cli\u003eCopper discharge and unloader tube (installed)\u003c\/li\u003e\n\u003cli\u003ePressure switch (installed)\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eAvailable Configurations — 7.5HP 3-Phase Industrial Lineup\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eI733HC1-S:\u003c\/strong\u003e 7.5HP, 3-phase, 30-gal horizontal, C1 pump, 895 RPM, 24.8 CFM@175PSI, magnetic starter\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eI733HC2-S (this unit):\u003c\/strong\u003e 7.5HP, 3-phase, 30-gal horizontal, C2 pump, 585 RPM, 28.1 CFM@175PSI, magnetic starter\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eI738HC1-S:\u003c\/strong\u003e 7.5HP, 3-phase, 80-gal horizontal, C1 pump, 895 RPM, 24.8 CFM@175PSI — 64x20x48 in., 625 lbs\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eI738HC2-S:\u003c\/strong\u003e 7.5HP, 3-phase, 80-gal horizontal, C2 pump, 585 RPM, 28.1 CFM@175PSI — 64x20x46 in., 730 lbs\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eI7312HC2-S:\u003c\/strong\u003e 7.5HP, 3-phase, 120-gal horizontal, C2 pump — maximum reserve capacity\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eWhen Does a Shop Need This vs. Stepping Up or Down\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eChoose the I733HC2-S\u003c\/strong\u003e when you need more CFM than the C1 delivers but still want the compact 30-gallon horizontal tank. The extra 3.3 CFM at working pressure is meaningful for shops running DA polishers, spray guns, or heavier hand tools alongside conventional impact and ratchet work.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eStep up to I738HC2-S\u003c\/strong\u003e if you need both the higher CFM of the C2 pump AND more air reserve — the 80-gallon tank gives you longer duty cycles between compressor runs. If you're painting cars or doing sustained sandblasting, the 80-gallon tank is the better call.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eStep down to I733HC1-S\u003c\/strong\u003e if your shop's sustained demand is lower — general automotive service with impacts, ratchets, and tire work doesn't always need the C2's extra CFM, and the C1 is a lighter, simpler unit.\u003c\/p\u003e\n\n\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eModel:\u003c\/strong\u003e I733HC2-S\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHorsepower:\u003c\/strong\u003e 7.5 HP\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePhase:\u003c\/strong\u003e 3-phase\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTank Capacity:\u003c\/strong\u003e 30 gallons\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTank Type:\u003c\/strong\u003e Horizontal, ASME-rated, powder coated\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePump Model:\u003c\/strong\u003e C2 (two-stage, cast iron, V4)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePump RPM:\u003c\/strong\u003e 585\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCFM @ 0 PSI:\u003c\/strong\u003e 35.0\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCFM @ 175 PSI:\u003c\/strong\u003e 28.1\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMax Working Pressure:\u003c\/strong\u003e 175 PSI\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMotor Speed:\u003c\/strong\u003e 1,725 RPM\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePump Stage:\u003c\/strong\u003e Two-stage\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePump Cylinder Configuration:\u003c\/strong\u003e V4\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStarter:\u003c\/strong\u003e Factory-mounted magnetic motor starter included\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDischarge Tube:\u003c\/strong\u003e Copper\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBelt Guard:\u003c\/strong\u003e Metal, fully enclosed\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhy Buy From Air Compressor Factory Direct?\u003c\/h3\u003e\n\u003cp\u003eWe've specialized in industrial and commercial air compressors since 2016. When you call, you're talking to someone who can explain why the C2 pump's lower RPM matters for your shop's longevity expectations, whether 30 gallons is enough reserve for your tools, and what electrical service you'll need to run this unit. Free shipping, free tech support at 866-217-0063, and the full Castair manufacturer warranty. Call us before you buy if you're comparing configurations.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eCall 866-217-0063 for quick answers and help!\u003c\/strong\u003e\u003c\/p\u003e","brand":"Cast Air","offers":[{"title":"Default Title","offer_id":53342569234645,"sku":"I733HC2-S","price":8071.28,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0622\/8466\/0949\/files\/I733HC2-S.jpg?v=1772675191","url":"https:\/\/aircompressorfactorydirect.com\/products\/castair-7hp-3-phase-industrial-air-compressor-horizontal-tank-w-mounted-starter-i733hc2-s","provider":"Air Compressor Factory Direct","version":"1.0","type":"link"}