{"product_id":"castair-d7124hc1-s","title":"Castair D7124HC1-S","description":"\u003cp\u003eThe Castair D7124HC1-S is a 15HP (2×7.5HP) single-phase duplex air compressor on a 240-gallon horizontal ASME tank with twin C1 cast iron pumps running at 895 RPM. This configuration is for single-phase shops that need both substantial air storage and full backup redundancy in one machine. The jump from a 120-gallon tank to a 240-gallon tank does not change the output — you still get 49.6 CFM at 175 PSI — but it changes how often your pumps cycle and how well the system handles peak demand spikes.\u003c\/p\u003e\n\n\u003cp\u003eAt 2,140 lbs., the D7124HC1-S is a substantial piece of equipment. Plan accordingly: floor load capacity, permanent mounting position, and a nearby electrical panel capable of supplying two 7.5HP single-phase motors. This is a machine you install once and run for 20 years. It earns its floor space by keeping your shop operational even when one pump is out for service.\u003c\/p\u003e\n\n\u003ch2\u003eWho Needs the D7124HC1-S\u003c\/h2\u003e\n\u003cp\u003eAuto body shops, commercial service centers, and production facilities on single-phase power that need both large tank volume and duplex reliability. If your shop runs sustained air tool demand — multiple body technicians, spray booths, automated equipment — the 240-gallon tank means your pumps cycle less frequently, stay cooler, and last longer. The C1 pump at 895 RPM delivers 49.6 CFM at 175 PSI, which supports three to four simultaneous air tool operators without meaningful pressure drop.\u003c\/p\u003e\n\n\u003cp\u003eShops that use air-intensive intermittent equipment (sandblasters, plasma cutters, automated spray systems) especially benefit from the 240-gallon reserve. When that equipment hits peak draw, the larger tank absorbs the surge without immediately cycling the pumps back on.\u003c\/p\u003e\n\n\u003ch2\u003eCastair C1 Pump Features\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eAll cast iron construction:\u003c\/strong\u003e Cylinders, crankcase, and valve plates are cast iron throughout. Cast iron runs cooler, quieter, and longer than aluminum under sustained industrial loads.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e895 RPM operating speed:\u003c\/strong\u003e The C1 pump runs at 895 RPM — roughly half the speed of many commodity compressor pumps — for reduced heat generation and longer service life.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTapered roller bearings:\u003c\/strong\u003e Both ends of the crankshaft use tapered roller bearings for superior crankshaft support under the radial and axial loads of reciprocating operation.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePrecision steel connecting rods:\u003c\/strong\u003e Automotive-type rod insert bearings at the crankshaft and bearings at the wrist pin. This is the engineering approach that separates long-life industrial pumps from short-life commodity pumps.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDisc and spring valves:\u003c\/strong\u003e More reliable than reed valves under continuous duty, and easier to service in the field. When valves wear, you replace the valves — not the pump head.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e4-ring pistons:\u003c\/strong\u003e Four rings per piston for higher compression efficiency and lower oil carry-over into the air supply. Two-ring pistons are common in budget pumps; four rings are not.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCentrifugal unloader:\u003c\/strong\u003e Loadless start on every cycle. The pump reaches operating speed before the compression load engages, reducing motor stress and extending motor life significantly in high-cycle applications.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eTank, Motor, and Control Features\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e240-gallon horizontal ASME tank:\u003c\/strong\u003e Powder-coated steel with channel base for stability. ASME certified pressure vessel — the certification covers design, construction, and materials, not just a stamp applied after the fact.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eASME safety valves:\u003c\/strong\u003e Certified pressure relief. Factory-original certified components — not field replacements.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFully enclosed metal belt guard:\u003c\/strong\u003e Meets OSHA safety requirements and keeps debris out of the drive system.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCopper discharge and unloader tube or stainless-steel braided flex line:\u003c\/strong\u003e Heat and pressure path components are copper or stainless. No plastic in the discharge circuit.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHeavy-duty 1725 RPM industrial motors:\u003c\/strong\u003e Full 15% service factor or higher. Built for continuous commercial use, not residential or light commercial cycles.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMagnetic starter mounted and wired (-S models):\u003c\/strong\u003e Factory-installed, factory-wired magnetic motor starters. You run your electrical supply to the panel connection — the internal wiring is done.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003e240-Gallon vs. 120-Gallon: Why the Bigger Tank Matters\u003c\/h2\u003e\n\u003cp\u003eBoth the 120-gallon (D7112HC1-S) and 240-gallon (D7124HC1-S) deliver the same 49.6 CFM at 175 PSI. The difference is cycle frequency and peak demand buffering. A 240-gallon tank takes twice as long to drop from cut-out pressure to cut-in pressure under the same air draw, which means the pumps cycle less often. Fewer cycles per hour means lower operating temperatures, less wear, and lower electrical costs from reduced motor starting frequency. If your shop runs air tools continuously for hours at a stretch, the 240-gallon tank will noticeably extend pump and motor life compared to the 120-gallon version.\u003c\/p\u003e\n\n\u003ch2\u003eFactory-Mounted Options Available\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eLow Oil Control (#6304x2M):\u003c\/strong\u003e Automatic shutdown before pump oil starvation can cause internal damage.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHour Meter (#HRM75x2M for 230V):\u003c\/strong\u003e Track actual operating hours for both pump units. Essential for maintenance interval scheduling.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAlternator (#ALT230M):\u003c\/strong\u003e Automatically rotates which pump leads each cycle to equalize run hours between units over time.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eElectronic Auto Drain (#SDV03M):\u003c\/strong\u003e Timer-controlled condensate drain. Tanks that are not drained daily accumulate moisture and corrode internally. This prevents that maintenance failure.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDual Control (#DC1x2M for C1 pumps):\u003c\/strong\u003e Enables unloaded continuous operation during high-demand periods to eliminate excessive motor starts. Motor inrush current at startup is 4 to 5 times running current — reducing starts directly reduces electrical costs and motor wear.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIntake Noise Silencers (#SA100x2M for C1):\u003c\/strong\u003e Inlet noise reduction without airflow restriction.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBelt Tensioner (#215Dx2M for 7.5-10HP):\u003c\/strong\u003e Spring-loaded belt tensioner prevents belt slippage and uneven wear as belts stretch over time.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRight From the Start Kit (#RFS001D for 10HP):\u003c\/strong\u003e Consolidated maintenance kit for first-service interval.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eVibration Pads (#VP1004):\u003c\/strong\u003e Isolation pads to reduce floor vibration transmission from the unit.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBelt Guard Aftercooler (#BGAC1x2M, 70 CFM for 10-20HP units):\u003c\/strong\u003e Reduces moisture in the air system by cooling compressed air before tank entry.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eAvailable Configurations — 7.5HP Single-Phase Duplex\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eD7112HC1-S:\u003c\/strong\u003e 2×7.5HP, single-phase, C1 pump (895 RPM), 120-gal, 49.6 CFM@175 PSI, 1,240 lbs. — same CFM, smaller tank, lower weight.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eD7112HC2-S:\u003c\/strong\u003e 2×7.5HP, single-phase, C2 pump (585 RPM), 120-gal, 56.2 CFM@175 PSI, 1,430 lbs. — more CFM, slower pump, 120-gal tank.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eD7124HC1-S (this unit):\u003c\/strong\u003e 2×7.5HP, single-phase, C1 pump (895 RPM), 240-gal, 49.6 CFM@175 PSI, 2,140 lbs. — same pump output with maximum air storage.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eD7124HC2-S:\u003c\/strong\u003e 2×7.5HP, single-phase, C2 pump (585 RPM), 240-gal, 56.2 CFM@175 PSI, 1,780 lbs. — maximum output with maximum storage.\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\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eStep down (D7112HC1-S, 120-gallon):\u003c\/strong\u003e If floor space is constrained or your air demand does not justify 240 gallons of storage, the 120-gallon version saves floor space and 900 lbs. Same pumps, same output, more frequent cycling.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThis unit (D7124HC1-S):\u003c\/strong\u003e Single-phase power, need for backup redundancy, shop runs sustained air demand through the workday, and floor space allows a 240-gallon footprint. The right machine for a serious single-phase shop that wants low cycle frequency and long pump life.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStep up (C2 pump or three-phase):\u003c\/strong\u003e If you need 56 CFM instead of 49.6 at 175 PSI, the D7124HC2-S uses the same 240-gallon tank with the C2 pump upgrade. If your facility has three-phase power, the D7324HC1-S (3-phase, C1, 240-gallon) delivers the same output at lower amp draw.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eModel:\u003c\/strong\u003e D7124HC1-S\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eConfiguration:\u003c\/strong\u003e Duplex (2 pumps, 2 motors)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMotor:\u003c\/strong\u003e 2×7.5HP, 15HP total\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePhase:\u003c\/strong\u003e Single-phase\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePump Series:\u003c\/strong\u003e C1 (cast iron)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePump RPM:\u003c\/strong\u003e 895\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCFM @ 0 PSI:\u003c\/strong\u003e 64.8\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCFM @ 175 PSI:\u003c\/strong\u003e 49.6\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTank:\u003c\/strong\u003e 240-gallon horizontal ASME\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDimensions (L×W×H):\u003c\/strong\u003e 85 × 30 × 64 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e 2,140 lbs.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMagnetic Starter:\u003c\/strong\u003e Included, factory-mounted and wired\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMax Pressure:\u003c\/strong\u003e 175 PSI\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhy Buy From Air Compressor Factory Direct?\u003c\/h3\u003e\n\u003cp\u003eWe have been selling and supporting professional-grade air compressors since 2016. We carry the full Castair duplex lineup — every HP class, both pump series, all tank sizes, in single-phase and three-phase. Free shipping on all orders. Free tech support at 866-217-0063 — call if you want help comparing tank sizes, calculating whether your electrical service supports this unit, or deciding between C1 and C2 pump configurations for your workload. Full manufacturer warranty and honest guidance.\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":53342541807829,"sku":"D7124HC1","price":17944.54,"currency_code":"USD","in_stock":true}],"url":"https:\/\/aircompressorfactorydirect.com\/products\/castair-d7124hc1-s","provider":"Air Compressor Factory Direct","version":"1.0","type":"link"}