The Castair BGAC2x2M is a duplex belt guard aftercooler — two BGAC2 cores mounted together as a single assembly for twin-pump reciprocating compressor installations or applications requiring 100 CFM total aftercooling capacity. It uses the same proven 50 CFM core as the BGAC2M, doubled up in a single mounted package.
Duplex compressors — two-pump units on a common base frame — produce discharge air from two separate cylinder heads. Without aftercooling on both discharge points, hot air from one or both pumps bypasses the cooling step and carries full moisture load downstream. The BGAC2x2M handles both discharge lines in a single unit, keeping the installation compact and maintaining consistent treatment across both pumps.
The BGAC2x2M is also the right choice when you need more total aftercooling capacity than a single BGAC2M provides. Two cores delivering 50 CFM each handle 100 CFM total, which covers larger single-pump compressors or combined output from multiple machines feeding a common header.
Core Performance Specifications — Per Unit and Combined
- CFM Rating Per Core: 50 CFM each
- Total CFM Capacity: 100 CFM (two cores operating in parallel)
- Rated Inlet Air Temperature: 250°F (performance figures based on this inlet condition per core)
- Maximum Operating Pressure: 250 PSIG
- Maximum Operating Temperature: 350°F
- Cooling Performance: Each core cools air to within 15°F above ambient temperature
- Moisture Reduction: Up to 65% reduction in water content per core
- Moisture physics: Water content in compressed air decreases approximately 50% for every 20°F temperature reduction. A 150–200°F drop through the aftercooler produces the 65% moisture reduction figure.
Physical Dimensions and Connections
- Aftercooler Core Size (each): 18 in L x 14-1/4 in W
- Number of Cores: 2 (duplex)
- Inlet Connections: Two 1 in NPT inlets (one per core)
- Outlet Connections: Two 1 in NPT outlets (one per core)
- Configuration: Duplex mounted — both cores pre-assembled to a common mounting panel
When to Use a Duplex Aftercooler vs. a Single-Core Unit
- Twin-pump compressors: A duplex reciprocating compressor has two cylinder heads producing compressed air simultaneously. Each discharge point needs aftercooling. Plumbing both through a single duplex aftercooler is cleaner than mounting two separate single-core units.
- Higher total CFM demand: If your system requires more than 50 CFM of aftercooled air, the BGAC2x2M gives you 100 CFM capacity in a single mounted assembly. This is relevant for larger single-pump compressors that exceed the BGAC2''s 50 CFM rating, or for combined-output situations.
- Space efficiency: Two cores in one mounted assembly takes less space and requires less high-temperature plumbing than two independent aftercooler units installed separately.
- Single-pump compressors below 50 CFM: The BGAC2x2M is overkill for a single 15 HP single-pump machine. Use the BGAC2M for that application.
How Belt Guard Aftercoolers Work
- Air-cooled operation: Each BGAC2 core in the duplex assembly sits in the path of the compressor flywheel fan''s airflow. The fan drives cooling air across both cores simultaneously — no separate blower required.
- Discharge-point cooling: Hot compressed air exits each cylinder head and passes through its respective aftercooler core before entering the receiver or distribution system. Moisture condenses at the aftercooler, not inside tanks and lines downstream.
- Condensate management: Each core produces condensate at its outlet. Install moisture separators at both outlets with drain valves — automatic float drains are preferred for continuous operation. Manual drains require scheduled attention.
- Independent circuits: Each core in the BGAC2x2M handles its own discharge line independently. The two air streams are not mixed within the aftercooler — they pass through separate internal passages and exit through separate outlet connections.
Installation Notes
- Two independent plumbing runs: Each core has its own 1 in NPT inlet and outlet. You will need to plumb two separate high-temperature discharge lines from the compressor to the aftercooler inlets, and two outlet lines from the aftercooler to the receiver or manifold.
- Fan airflow positioning: The duplex assembly must be positioned so both cores receive adequate airflow from the compressor flywheel fan. Proper positioning is critical — if one core is outside the main fan airflow, it will underperform.
- High-temperature inlet plumbing: From cylinder head to aftercooler inlet, use pipe or hose rated for 250 PSIG and 350°F. Standard rubber air hose is not appropriate for this section.
- Condensate drains: Install drains at the lowest points after each aftercooler outlet. One automatic drain per core is the right setup for continuous operation.
- Fitment verification: Call 866-217-0063 before ordering if you are not certain the BGAC2x2M mounting panel fits your specific compressor frame. Duplex compressor frames vary in belt guard panel size and configuration.
Technical Specifications
- SKU: BGAC2x2M
- Manufacturer: Cast Air (Castair)
- CFM Capacity Per Core: 50 CFM
- Total CFM Capacity: 100 CFM (duplex)
- Core Dimensions (each): 18 in L x 14-1/4 in W
- Number of Cores: 2
- Inlet Connections: Two 1 in NPT
- Outlet Connections: Two 1 in NPT
- Maximum Pressure: 250 PSIG
- Maximum Temperature: 350°F
- Rated Inlet Temperature: 250°F (per core)
- Cooling to: Within 15°F of ambient temperature (per core)
- Moisture Reduction: Up to 65% per core
- Configuration: Duplex mounted (two cores on common mounting panel)
Available Configurations — Full BGAC Series Lineup
Cast Air belt guard aftercoolers are available in four sizes plus duplex configurations:
- 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 / BGAC2K — 50 CFM: 18 in x 14-1/4 in core, 1 in NPT connections, 12 lbs. Fits 15 HP. Available as loose core (BGAC2), mounted (BGAC2M), kit (BGAC2K).
- BGAC2x2M — 100 CFM Duplex (this unit): Two BGAC2 cores on a common mounting panel. For duplex compressors or 100 CFM total capacity requirements.
- 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 single-pump systems.
For twin-pump duplex compressors, the BGAC2x2M is typically the correct choice over a single larger core — it gives you independent aftercooling for each pump discharge rather than combining flows before aftercooling.
When Does a Shop Need This vs. Stepping Up or Down
- BGAC2x2M is right for you if: You have a duplex (twin-pump) 15 HP reciprocating compressor with two discharge points, or if your system requires 100 CFM of aftercooled air and you want a compact dual-core assembly.
- Use BGAC2M instead if: You have a single-pump 15 HP compressor. The single-core BGAC2M is correctly sized and less expensive.
- Step up to BGAC3 or BGAC4 series if: Your compressor is a single-pump unit rated above 50 CFM. A single larger core from the BGAC3 or BGAC4 series may be more appropriate than a duplex of 50 CFM cores for a single discharge point.
- Call us if you are unsure: Duplex compressor configurations vary significantly. If you are not certain whether you need the BGAC2x2M or a single larger aftercooler, call 866-217-0063 and describe your compressor setup. We will point you to the right solution.
Why Buy From Air Compressor Factory Direct
- Specialist since 2016: Compressed air equipment is our focus — compressors, aftercoolers, dryers, separators, and accessories. We do not sell compressed air as a footnote to a general industrial catalog.
- Free shipping: Orders to the continental United States ship free, including larger assemblies like the BGAC2x2M.
- Free tech support: Call 866-217-0063. We can help you confirm the BGAC2x2M is the right configuration for your specific duplex compressor, verify connection sizing, and walk through condensate drain placement for a dual-core installation.
- Full manufacturer warranty: Cast Air factory warranty on all BGAC series aftercoolers.
- Honest configuration guidance: If the BGAC2x2M is not the right fit for your compressor setup — wrong core count, wrong size, wrong configuration — we will tell you before the order ships.
Call 866-217-0063 for quick answers and help!
