Beltguard Aftercooler - BGAC2M – 50cfm (15hp)

The Castair BGAC2M is a 50 CFM belt guard aftercooler rated for 15 HP reciprocating air compressors. This listing makes the horsepower and CFM rating explicit — this is the same BGAC2M mounted aftercooler assembly, specified here as the 50 CFM / 15 HP configuration so there is no ambiguity when ordering for a specific compressor. It cools compressor discharge air to within 15°F of ambient temperature and reduces water content in the compressed air stream by up to 65%. The mounted design means the aftercooler core comes pre-assembled on a belt guard mounting panel. It bolts directly onto the belt guard of your 15 HP reciprocating compressor and sits in the path of the flywheel fan''s cooling airflow. Plumb the compressor discharge to the 1 in NPT inlet, run the outlet to your receiver tank, and the aftercooler is operational. No bracket fabrication, no custom positioning. If you are shopping this listing because you specifically searched for a 50 CFM aftercooler for a 15 HP compressor, this is the correct unit. The BGAC2M handles that exact application. Core Performance Specifications CFM Rating: 50 CFM — explicitly rated for 15 HP reciprocating compressors Horsepower Match: 15 HP Rated Inlet Air Temperature: 250°F Maximum Operating Pressure: 250 PSIG Maximum Operating Temperature: 350°F Cooling Performance: Cools compressor discharge air to within 15°F above ambient temperature Moisture Reduction: Up to 65% reduction in water content Why 65%: Water content in compressed air drops approximately 50% for every 20°F temperature reduction. The BGAC2M typically reduces air temperature by 150–200°F, which yields the 65% moisture reduction figure. The exact amount depends on ambient conditions and actual inlet temperature. Physical Dimensions and Connections Core Size: 18 in L x 14-1/4 in W Inlet Connection: 1 in NPT Outlet Connection: 1 in NPT Weight: 12 lbs Configuration: Mounted — pre-assembled to belt guard mounting panel, ready for direct compressor installation Price: $611.95 Why Add an Aftercooler to a 15 HP Compressor The moisture problem: A 15 HP reciprocating compressor running at 100 PSIG and 50 CFM passes a significant volume of air through the compression cycle. At discharge temperatures of 200–350°F, nearly all the water vapor in that air stays airborne. It travels into your receiver tank, your distribution lines, and your tools. What that moisture does: Water in compressed air causes rust inside receiver tanks, valve failure in pneumatic controls, water in spray gun air (which ruins paint finishes), corrosion in air tools, and water spray from blow guns. All of these are symptoms of the same root cause — uncooled, wet compressed air. What the aftercooler does: The BGAC2M cools the discharge air to near ambient temperature immediately after it leaves the compressor cylinder head. At ambient temperature, most of the water vapor condenses into liquid and can be drained off before it enters the distribution system. A downstream moisture separator catches the condensate. The correct sequence: Compressor discharge → BGAC2M aftercooler → moisture separator with drain → receiver tank → distribution system. This sequence handles the moisture where it is easiest to manage — at the source — rather than trying to clean it up throughout the distribution system. How the Mounted Design Works Belt guard positioning: The mounting panel positions the aftercooler core directly in the compressor flywheel fan''s airflow. The fan runs whenever the compressor runs, continuously pulling ambient air across the core fins and removing heat from the compressed air passing through the internal passages. No external power: The cooling fan is the compressor''s own flywheel fan. No separate blower motor, no additional electrical connection. Compact footprint: Mounting directly on the belt guard keeps the aftercooler close to the compressor frame and minimizes the length of high-temperature discharge piping needed between the cylinder head and the aftercooler inlet. Installation Notes Bolt-on mounting: The BGAC2M mounts to the belt guard panel of a standard 15 HP reciprocating compressor. Verify your compressor frame and belt guard dimensions are compatible — call 866-217-0063 if you need fitment confirmation for a specific model. High-temperature discharge plumbing: The section from the compressor cylinder head discharge port to the aftercooler inlet must be plumbed with materials rated for 250 PSIG and 350°F — hard copper or steel pipe, or high-temperature flexible hose. Standard rubber air hose is not rated for this temperature range. Outlet plumbing: Air leaving the aftercooler is near ambient temperature. Standard compressed air fittings and hose are appropriate on the outlet side. Condensate drain: Install a moisture separator with an automatic float drain at the aftercooler outlet. This captures the condensate and removes it from the system without manual attention. A manual ball valve drain works but requires scheduled operation. Technical Specifications SKU: BGAC2M Manufacturer: Cast Air (Castair) CFM Capacity: 50 CFM HP Rating: 15 HP Core Dimensions: 18 in L x 14-1/4 in W Inlet Connection: 1 in NPT Outlet Connection: 1 in NPT Weight: 12 lbs Maximum Pressure: 250 PSIG Maximum Temperature: 350°F Rated Inlet Temperature: 250°F Cooling to: Within 15°F of ambient temperature Moisture Reduction: Up to 65% Configuration: Mounted (pre-assembled to belt guard mounting panel) Price: $611.95 Available Configurations — Full BGAC Series Lineup Cast Air makes belt guard aftercoolers in four sizes. Choose based on your compressor''s horsepower and CFM output: BGAC1 / BGAC1M — 35 CFM: 18 in x 10-1/2 in core, 3/4 in NPT connections, 8 lbs. Fits 5, 7, and 10 HP compressors. BGAC2 / BGAC2M — 50 CFM (this unit): 18 in x 14-1/4 in core, 1 in NPT connections, 12 lbs. Fits 15 HP. Available as loose core (BGAC2, $464.31), mounted assembly (BGAC2M, $611.95), or kit with hardware (BGAC2K). Duplex version: BGAC2x2M. BGAC3 / BGAC3M — 75 CFM: 24 in x 20-1/2 in core, 1 in NPT connections, 20 lbs. Fits 20+ HP compressors. BGAC4 / BGAC4M — 100 CFM: 23 in x 26-1/2 in core, 1 in NPT connections, 25 lbs. For larger systems. The BGAC2M is sized specifically for 15 HP. Do not use a 35 CFM BGAC1 core on a 15 HP machine — the air velocity through the undersized core will be too high for adequate cooling. The BGAC3 series (75 CFM) is appropriate for 20 HP and above. When Does a Shop Need This vs. Stepping Up or Down BGAC2M is correct for you if: You have a 15 HP reciprocating compressor, you are seeing moisture downstream (water in lines, tool failures, rusty tanks, water in spray air), and you want a factory-mounted aftercooler that installs directly on the belt guard without custom fabrication work. Choose BGAC2 (loose core) instead if: You are doing a custom installation, replacing an existing core, or your compressor''s belt guard geometry does not match the standard BGAC2M mounting panel. Choose BGAC2K instead if: You want the aftercooler core plus mounting hardware but prefer to do the final assembly and installation yourself rather than receiving a pre-assembled unit. Choose BGAC2x2M instead if: You have a duplex (twin-pump) compressor with two discharge points, or if your system requires 100 CFM total aftercooling capacity. Step down to BGAC1M if: Your compressor is 10 HP or smaller. Step up to BGAC3M if: Your compressor is rated above 15 HP, or if you are consistently running a 15 HP machine at maximum capacity in high ambient temperature conditions and want more cooling margin. Why Buy From Air Compressor Factory Direct Specialist since 2016: Compressed air equipment is our specialty — compressors, aftercoolers, dryers, separators, and accessories. Not a general industrial distributor. Free shipping: All orders to the continental United States ship free. Free tech support: Call 866-217-0063. We can confirm this unit fits your specific compressor model, explain the full installation sequence, and help you plan condensate drain placement. Full manufacturer warranty: Cast Air factory warranty. No gray-market or diverted stock. Sizing honesty: If the BGAC2M is not the right aftercooler for your compressor, we will say so before you order. Call 866-217-0063 for quick answers and help!