{"product_id":"heavy-duty-shop-tandem-model-no-t15312hc1-s","title":"Heavy Duty Shop Tandem - Model No.: T15312HC1-S","description":"\u003ch2\u003eCast Air Heavy Duty Shop Tandem Air Compressor — T15312HC1-S\u003c\/h2\u003e\n\u003cp\u003eThe T15312HC1-S is a two-stage twin-pump tandem from Cast Air running two 15 HP motors on 3-phase power, paired with a 120-gallon horizontal ASME tank. The HC1 configuration runs the cast iron pumps at 898 RPM, producing 110 CFM at 0 PSI and 90.6 CFM at 175 PSI from both pumps combined. At $6,675, this is the entry point into the 15 HP tandem lineup — the 120-gallon tank keeps the footprint manageable while still giving you enough receiver volume to handle peak air demand in a busy shop. If you are running tire mounting equipment, paint prep tools, or multiple air-powered lifts simultaneously, this configuration gives you the CFM without the premium of the larger tank or slower-RPM HC2 pump.\u003c\/p\u003e\n\n\u003ch3\u003eWhy Two Pumps?\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eRedundancy:\u003c\/strong\u003e One pump down does not shut down the shop. Service the failed side while the working pump carries the load.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLoad sharing:\u003c\/strong\u003e Two 15 HP pumps sharing demand run cooler than one 30 HP unit under the same total load.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAlternator option:\u003c\/strong\u003e Add the ALT230M or ALT460M relay and the system automatically alternates which pump leads each cycle, keeping runtime hours equal on both sides.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eCast Iron Pump Features\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eAll cast iron pump construction:\u003c\/strong\u003e Cylinders, heads, and crankcase are cast iron for thermal stability and long service life.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e898 RPM (HC1 configuration):\u003c\/strong\u003e The HC1 pump runs at a higher RPM than the HC2 — more CFM per pump size, but still dramatically slower than the 1,200–1,800 RPM pumps found in import equipment.\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 and reduced friction.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePrecision steel connecting rods:\u003c\/strong\u003e Automotive-type insert bearings at the crankshaft, needle bearings at the wrist pin.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDisc and spring valves:\u003c\/strong\u003e Serviceable in the field. More reliable than reed valves and easier to rebuild.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e4-ring pistons:\u003c\/strong\u003e Higher efficiency, less oil carry-over into the discharge air.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCentrifugal unloader:\u003c\/strong\u003e Loadless start every time. The unloader bleeds head pressure before startup, protecting motors and pressure switches from hard starts.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eTank and Controls\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e120-gallon horizontal ASME tank:\u003c\/strong\u003e Powder-coated, channel base. The 120-gallon tank is the right size when shop footprint matters and your demand spikes are short — the two pumps recover quickly enough that 120 gallons is adequate for most shop workflows.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTwo magnetic motor starters — mounted and wired:\u003c\/strong\u003e Factory-installed on both pump sides. Connect to your 3-phase panel and operate.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eASME safety valves:\u003c\/strong\u003e Set to factory-spec relief pressure on both sides.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMetal belt guards:\u003c\/strong\u003e Fully enclosed on both pump assemblies.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCopper discharge and unloader tubes:\u003c\/strong\u003e Heat-resistant copper tubing, not rubber hose.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e1,725 RPM industrial motors:\u003c\/strong\u003e Full 15% service factor or higher.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eAvailable Factory-Mounted Options\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eLow Oil Control (#6304x2M):\u003c\/strong\u003e Auto-shutdown on low oil for both pumps.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHour Meter 230V (#HRM75x2M) or 460V (#HRM460x2M):\u003c\/strong\u003e Track runtime on each pump independently.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAlternator Relay (#ALT230M or #ALT460M):\u003c\/strong\u003e Automatically alternates lead pump each cycle.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eElectronic Auto Drain (#SDV03M):\u003c\/strong\u003e Timed solenoid condensate drain.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDual Control (#DC1x2M):\u003c\/strong\u003e Start\/stop and throttle control modes (HC1 units use DC1 designation).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIntake Noise Silencers (#SA100x4M):\u003c\/strong\u003e Reduces intake noise on both pumps.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBelt Tensioner (#254Dx2M for 15 HP):\u003c\/strong\u003e Self-tensioning motor base.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAftercooler (#BGAC1x2M, 70 CFM rated):\u003c\/strong\u003e Belt-guard-mounted aftercooler for both pump sides.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAll Options Package (#AOC1D):\u003c\/strong\u003e Order all asterisk options together and receive 10% off.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhat Is in the Box\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eTwo cast iron two-stage pump and motor assemblies on a single rigid frame\u003c\/li\u003e\n\u003cli\u003e120-gallon horizontal powder-coated ASME tank with channel base\u003c\/li\u003e\n\u003cli\u003eTwo magnetic motor starters, mounted and wired at the factory\u003c\/li\u003e\n\u003cli\u003eTwo ASME safety valves\u003c\/li\u003e\n\u003cli\u003eTwo metal belt guards (fully enclosed)\u003c\/li\u003e\n\u003cli\u003eCopper discharge and unloader tubes on both sides\u003c\/li\u003e\n\u003cli\u003ePressure switch for each pump\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cem\u003eOptional accessories are factory-installed at time of order and are not included unless specified at purchase.\u003c\/em\u003e\u003c\/p\u003e\n\n\u003ch3\u003eAvailable Configurations — 15 HP Shop Tandem Lineup\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eT15312HC1-S:\u003c\/strong\u003e 2×15 HP, 898 RPM, 110 CFM \/ 90.6 CFM @ 175 PSI, 120-gal — $6,675 (this unit)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eT15312HC2-S:\u003c\/strong\u003e 2×15 HP, 795 RPM, 123.4 CFM \/ 100.4 CFM @ 175 PSI, 120-gal — $7,639 (larger pump, more CFM)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eT15324HC1-S:\u003c\/strong\u003e 2×15 HP, 898 RPM, 110 CFM \/ 90.6 CFM @ 175 PSI, 240-gal — $8,121 (larger tank for bigger demand spikes)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eT15324HC2-S:\u003c\/strong\u003e 2×15 HP, 795 RPM, 123.4 CFM \/ 100.4 CFM @ 175 PSI, 240-gal — $9,173 (maximum 15 HP configuration)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eThe HC1 configuration gives you 898 RPM pump speed and 110 CFM combined — the HC2 steps up to 795 RPM (slower, quieter, longer life) and 123.4 CFM. If your shop consistently runs at or near capacity, the HC2 is worth the additional cost. If you have shorter peaks with recovery time, the HC1 on a 120-gallon tank handles it for less money.\u003c\/p\u003e\n\n\u003ch3\u003eWhen Does a Shop Need This vs. Stepping Up or Down?\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eStep down:\u003c\/strong\u003e If your shop runs two or three air tools at once and your current 7.5 HP compressor keeps up most of the time, you do not need a 15 HP tandem. A single 10 HP or 15 HP industrial unit handles that load with less capital cost.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThis unit is right when:\u003c\/strong\u003e You are running a 4–6 bay shop where multiple technicians use air tools simultaneously, or a tire shop with mounting and balancing equipment plus impact guns going at once. The 90.6 CFM at 175 PSI sustained output means your system pressure stays stable while every bay is working.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStep up:\u003c\/strong\u003e Body shops running full spray booths, shops with dedicated CNC air-powered equipment, or operations needing 100+ CFM continuously should look at the 20–30 HP tandem models or Cast Air's rotary screw line.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eTechnical Specifications — T15312HC1-S\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eModel Number:\u003c\/strong\u003e T15312HC1-S\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHorsepower:\u003c\/strong\u003e 2 × 15 HP (30 HP total)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePhase:\u003c\/strong\u003e 3-phase\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePump RPM:\u003c\/strong\u003e 898 (HC1 configuration)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCFM @ 0 PSI:\u003c\/strong\u003e 110 (combined, both pumps)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCFM @ 175 PSI:\u003c\/strong\u003e 90.6 (combined, both pumps)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTank Capacity:\u003c\/strong\u003e 120 gallons, horizontal\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTank Type:\u003c\/strong\u003e ASME-certified, powder-coated, channel base\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMotor Speed:\u003c\/strong\u003e 1,725 RPM, 15% service factor\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePump Type:\u003c\/strong\u003e Two-stage, all cast iron, centrifugal unloader\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eControls:\u003c\/strong\u003e Two magnetic motor starters, mounted and wired\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDischarge Tubing:\u003c\/strong\u003e Copper\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBelt Guard:\u003c\/strong\u003e Metal, fully enclosed\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePrice:\u003c\/strong\u003e $6,674.80\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cem\u003eNote: Exact LxWxH dimensions and shipping weight for this tandem configuration are not published individually by Castair. Contact us for freight details before ordering.\u003c\/em\u003e\u003c\/p\u003e\n\n\u003ch3\u003eWhy Buy From Air Compressor Factory Direct?\u003c\/h3\u003e\n\u003cp\u003eWe have specialized in industrial air compressor sales since 2016. Cast Air's American-built, cast iron machines are a core part of our lineup because they hold up where import equipment fails. When you buy through us:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eFree shipping\u003c\/strong\u003e to a commercial address with a loading dock or forklift\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFree tech support at 866-217-0063\u003c\/strong\u003e — we will help you choose between HC1 and HC2, and between the 120 and 240-gallon tank, based on your actual shop CFM demand\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFull Cast Air manufacturer warranty\u003c\/strong\u003e — we handle warranty claims directly with Cast Air on your behalf\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHonest upgrade guidance:\u003c\/strong\u003e We will tell you if a different configuration fits your shop better. We would rather sell you the right machine than the wrong one.\u003c\/li\u003e\n\u003c\/ul\u003e\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":53342603837653,"sku":"T15312HC1-S","price":6674.8,"currency_code":"USD","in_stock":true}],"url":"https:\/\/aircompressorfactorydirect.com\/products\/heavy-duty-shop-tandem-model-no-t15312hc1-s","provider":"Air Compressor Factory Direct","version":"1.0","type":"link"}