The Dunham Bush ACHX "Helios" Series is an advanced lineup of air-cooled horizontal rotary screw liquid chillers built for high-performance commercial and industrial process cooling. Scaling in cooling capacity from 90 to 590 RT ($315\text{ to }2073\text{ kW}$), this series features high-efficiency semi-hermetic horizontal screw compressors matched with flooded shell-and-tube evaporators. Specially engineered for rugged tropical conditions, selected models can operate effortlessly in extreme high-ambient temperatures reaching up to $52^\circ\text{C}$ to $55^\circ\text{C}$ ($125^\circ\text{F}\text{ to }131^\circ\text{F}$). It stands as the premier central cooling solution across Bangladesh for factories, pharmaceutical labs, and corporate high-rises where a reliable water grid is unavailable.
Cooling Capacity from 90 to 395 RT (317 to 1389kW)
The ACHX-B Series features:-
Cooling Capacity from 90 to 439 RT (317 to 1545 kW)
The ACHX-C features:
Cooling Capacity from 93 RT to 248 RT (329kW to 875kW)
The ACHX-D features:
Cooling Capacity from 94 RT to 249 RT (329kW to 875kW)
The ACHX-DVE features:
Cooling Capacity from 90TR to 418TR (315kW to 1470kW)
The ACHX-BH features:
Cooling Capacity from 123 to 590RT (432 to 2073kW).
The ACHX-BHVD features:
Cooling Capacity from 112 to 462RT (392 to 1626kW)
The ACHX-BVD Series features:
The horizontal orientation of the screw profiles achieves smooth, continuous gas compression with exceptionally low mechanical vibration and balanced bearing loads. This translates to silent operating profiles and vastly extended machine lifetimes.
For premium thermodynamic output, the ACHX series utilizes a flooded shell-and-tube evaporator. By submerging cleanable, inner-finned copper tubes entirely within a pool of liquid refrigerant, the design achieves ultra-low approach temperatures and maximizes heat exchange efficiency. The unit features a structural V-coil condenser layout to maximize air movement across the fins, ensuring compact spatial utilization without risking hot air recirculation.
| Feature / Variant Options | Technical Specification Details |
| Cooling Capacity Range | 90 to 590 RT ($315\text{ to }2073\text{ kW}$) |
| Compressor Technology | Semi-Hermetic Horizontal Screw (Single or Twin options) |
| Heat Exchanger Profile | Flooded shell-and-tube with removable water heads |
| Condenser Coil Builds | Copper tube / Aluminum slit fin (or All-Aluminum Micro-Channel options) |
| High Ambient Threshold | Engineered to run smoothly up to $52^\circ\text{C}$ to $55^\circ\text{C}$ ($125^\circ\text{F}\text{ to }131^\circ\text{F}$) |
| Primary Controller Matrix | DB Vision Microprocessor Controller with EEV liquid stabilization |
| Certifications & Compliance | AHRI Certified, ASHRAE 90.1 Compliant, Green Refrigerants |
Twin Circuit True Redundancy: Built with single or twin compressors across entirely independent refrigerant circuits. If one circuit requires scheduled service, the remaining loop continues to operate normally, preventing total facility cooling blackouts.
Infinite Slide Valve Loading: Utilizes an integrated internal slide valve mechanism that continuously moves to match the compression chamber volume with the actual building load. This delivers smooth, stepless modulation from $100\%$ capacity down to partial loads without sudden power cycling.
Advanced Economizer Cycle Efficiency: The refrigerant is sub-cooled at a dedicated economizer circuit prior to entering the evaporator. This flash-gas injection process noticeably raises the net cooling tonnage while generating only a marginal increase in total kilowatt input.
Variable Speed Integration (BVD / BHVD): Available optional configurations combine inverter-driven variable speed screw compressors and VFD condenser fans. This technology optimizes part-load energy efficiency (IPLV) during rainy spells, monsoon seasons, or cooler night shifts.
Public utility systems—such as national data registries, central banking complexes, public defense administrative centers, and government research laboratories—demand robust cooling that will not place a strain on surrounding natural resources.
Protects Groundwater Assets: Operating strictly on an air-cooled heat rejection framework, the ACHX series saves thousands of liters of fresh water daily by removing the need for cooling towers and chemical water treatments.
Weatherproof Safety Protection: Built with a heavy gauge, powder-coated sheet steel enclosure rated for outdoor installations, the electrical panel protects sensitive microprocessors against high humidity and intense tropical monsoons.
For commercial sectors—including high-density RMG (Ready-Made Garments) textiles, cleanroom pharmaceutical lines, and commercial multi-story properties—sustained internal climate regulation directly impacts operational output and workforce productivity.
Prevents Extreme Temperature Trips: With global warming breaking summer temperature records across Dhaka and Chittagong, the high-ambient ACHX variants guarantee uninterrupted operation at outdoor peaks up to $52^\circ\text{C}$ to $55^\circ\text{C}$.
Simplified, Economical Maintenance: The cleanable copper tubes inside the flooded evaporator feature fully removable water heads. Maintenance teams can easily sweep away mineral scaling left behind by local hard water sources without disrupting primary refrigerant circuits.
Procuring a high-tonnage central chiller plant requires experienced technical coordination. Bhai Bhai Engineering delivers professional HVAC sourcing and engineering capabilities in Bangladesh:
Authentic OEM Sourcing Guarantee: We deal directly with official factory distribution channels, providing brand-new, 100% genuine Dunham Bush machinery verified by clean factory serial number registries.
End-to-End Field Engineering Support: Our local technicians handle structural layout reviews, frame anchoring assistance, pipe testing, water flow balancing, and certified live start-up procedures.
Transparent BDT Commercial Proposals: We provide straightforward, upfront pricing in Bangladeshi Taka (BDT) with no hidden logistics surcharges, designed to integrate seamlessly into corporate procurement systems or public tender structures.
Local Spare Parts Coverage: We maintain quick local access to original electronic expansion valves (EEVs), microprocessor control boards, and preventative maintenance items to keep your facility operational.
Equip your commercial project with elite air-cooled cooling technology. Get in touch with our specialized project engineering sales desk in Dhaka today to get a detailed commercial proposal and technical product submittals.
Corporate Showroom & Office: Podirdia, Khilbarirtek, Vatera, Dhaka-1212. (Nur-E-Madina Mosjid Complex)
Sales Hotlines / WhatsApp:+8801722039029
Corporate Email: bhaibhaiengineering51@gmail.com
Engineering Platform: https://www.bhaibhaiengineering.com/
Q1: What are the main benefits of a horizontal screw compressor over a standard scroll chiller for mid-to-high loads?
Ans: Horizontal screw compressors are engineered for heavier, continuous industrial workloads. They offer infinitely variable capacity modulation via an internal slide valve, providing significantly greater energy efficiency, tighter temperature control, and a much longer machine life compared to cycling multiple small scroll motors.
Q2: How does the ACHX high-ambient design prevent thermal shutdown during severe Bangladeshi summer peaks?
Ans: The high-ambient variants (such as the ACHX-C and ACHX-BH lines) utilize specialized semi-hermetic horizontal compressors and oversized condenser surface configurations. This allows them to effectively reject heat and run smoothly even when outdoor ambient conditions reach $52^\circ\text{C}$ to $55^\circ\text{C}$.
Q3: Does the Dunham Bush ACHX series include built-in protection against grid power issues?
Ans: Yes. The state-of-the-art Vision microprocessor controller features proactive safety trip protections. It automatically senses phase reversals, under/over-voltage drops, and current imbalances, safely turning off the compressor loops to prevent motor burnout until power conditions return to a safe range.
Q4: Is it possible to isolate a single compressor loop for service while the rest of the building continues to cool?
Ans: Absolutely. Multi-compressor models are built with entirely independent refrigerant circuits per compressor. One circuit can undergo planned maintenance or a filter replacement while the adjacent loop operates at partial capacity, keeping your facility online.
At Bhai Bhai Engineering, we take pride in our industry-recognized certifications and achievements. Our dedication to excellence in MEP (Mechanical, Electrical, and Plumbing) solutions is backed by various certifications in central air conditioning systems, fire protection, ventilation, electrical installations, and more. These certifications ensure we meet international standards and deliver top-notch service for your business.
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