The Dunham Bush DMAR-Y Series is an advanced line of industrial-grade Exhaust and Hot Water Driven Multi-Energy Absorption Chillers. Delivering heavy-duty central cooling capacities from 150 to 2000 RT ($528\text{ to }7034\text{ kW}$) and heating outputs from 90 to 1196 RT, the DMAR-Y completely replaces high-amp mechanical compressor motors. Instead, it captures and uses the ultra-high-temperature exhaust gas ($750^\circ\text{F}\text{ to }1000^\circ\text{F}$) combined with the jacket hot water loop from captive gas generators or industrial engines. This eco-friendly, zero-electricity-cost central HVAC powerhouse is ideal for large RMG garment factories, textile mills, pharmaceutical processing zones, and co-generation facilities across Bangladesh.
Cooling Capacity from 150 – 2000RT / 528 – 7034kW
Heating Capacity from 90 – 1196RT / 315 – 4206 kW
The DMAR-Y features:
The Dunham Bush DMAR-Y Series Multi-Energy Absorption Chiller represents the absolute cutting edge of co-generation and tri-generation energy efficiency for large-scale industrial manufacturing in Bangladesh. In major industrial sectors like Gazipur, Savar, and Narayanganj, factories run independent, gas-fired captive generators around the clock to ensure steady electricity. Typically, these generators discharge massive amounts of thermal energy directly into the environment through high-temperature exhaust pipes and radiator jacket loops. The DMAR-Y captures both waste heat sources at the same time, feeding them into a high-performance absorption cycle to produce massive streams of chilled water for central air conditioning—completely free of monthly electricity utility costs.
Operating inside an airtight, deep vacuum shell, the chiller utilizes eco-friendly water as its primary refrigerant and non-toxic Lithium Bromide ($LiBr$) liquid salt as the chemical absorbent. Because water boils at an ultra-low temperature ($4.5^\circ\text{C}$) under extreme vacuum conditions, it strips away heat from your factory's building water loop with exceptional efficiency. The concentrated $LiBr$ solution acts as a strong chemical sponge to absorb this vapor. The incoming high-temperature generator exhaust gases and jacket hot water streams are then passed through the chiller’s generator tubes, boiling the water out of the solution so the fluid loop can run continuously.
To prevent typical industrial fouling issues, the DMAR-Y features a specialized gravity drip distribution technology. Instead of spraying the chemical solution forcefully under high pressure, the $LiBr$ liquid drops smoothly over the internal heat exchanger tubes, forming a uniform film that optimizes heat transfer. The entire plant is managed by an intelligent microprocessor panel featuring Variable Frequency Drive (VFD) solution pump controls. The system automatically tracks the fluctuating thermal output of your factory's engines, adjusting internal pump speeds in real time to match the exact cooling needs of your facility.
| Feature / Attribute | Technical Specification Details |
| Cooling Capacity Range | 150 to 2000 RT ($528\text{ to }7034\text{ kW}$) |
| Heating Capacity Range | 90 to 1196 RT ($315\text{ to }4206\text{ kW}$) |
| Energy Input Medium | Gas Generator Exhaust Gas + Engine Jacket Hot Water (Combined or Independent) |
| Refrigeration Fluids | Lithium Bromide ($LiBr$) Absorbent and Pure Water ($H_2O$) Refrigerant |
| Liquid Film Engineering | Advanced Gravity Drip Technology (Maximizes chemical surface contact) |
| Crystallization Shield | Multi-level automated dilution loops and real-time density calculation |
| Vacuum Maintenance | Fully automatic, high-capacity vacuum air-purging system |
| Eco Compliance | 100% ODP & GWP Free — Zero synthetic hydrofluorocarbon (HFC) chemical use |
Dual-Source Waste Heat Capture: Synchronizes input from both high-temperature exhaust gases and low-temperature engine jacket water to maximize cooling output from your existing machinery.
High-Efficiency Thermal Staging: Utilizes a double-generator chemical design to recapture internal thermal energy from the first stage, maximizing cooling output per unit of waste heat captured.
Automated Vacuum Maintenance: Features a high-capacity, fully automatic air purging system that instantly captures and purges non-condensable gases, keeping heat-transfer surfaces clean and preventing internal corrosion.
VFD Part-Load Energy Optimization: Uses variable-frequency drives on the internal solution pumps to adjust chemical flow rates based on changing indoor cooling loads, cutting energy use during off-peak hours.
State-run properties—including major international airport terminals, large public railway secretariats, public sector power generation plants, and national database server hubs—frequently operate heavy-duty captive generation equipment.
Lowers National Grid Congestion: By generating central HVAC comfort cooling directly from generator waste heat instead of multi-megawatt electric chillers, public facilities dramatically lower their strain on the local electrical grid.
Guaranteed Backup Cooling Security: Critical data infrastructure and control rooms can maintain full central cooling using backup generator lines, even during total electrical grid blackouts.
For Bangladesh's export-oriented Ready-Made Garment (RMG) factories, large spinning plants, and pharmaceutical cleanrooms, optimizing fuel efficiency is essential for global cost competitiveness.
Unlocks True Tri-Generation Savings: Factories running local gas generators can capture both exhaust and jacket hot water to run a DMAR-Y chiller, achieving near-zero operating costs for their central office or factory cooling.
Earns Premium Global Green Credentials: Implementing waste-heat recovery absorption chillers helps factories score maximum points on international green building frameworks (such as LEED), making your facility a preferred supplier for top global brands.
Procuring, designing, and commissioning a high-capacity multi-energy exhaust absorption chiller requires deep industrial HVAC expertise. Bhai Bhai Engineering delivers professional end-to-end technical support across Bangladesh:
Verified Authentic OEM Import Guarantee: We source directly through authorized global Dunham Bush manufacturing tracks, supplying 100% genuine, brand-new equipment complete with verified serial numbers and original factory warranties.
Turnkey Industrial Integration: Our experienced local engineering team manages the complete installation—including high-temperature exhaust gas duct interfacing, hydraulic balancing, cooling tower integration, and advanced automation tuning.
Transparent Local BDT Project Quotations: Avoid unexpected currency shifts or hidden import fees. We provide detailed, transparent financial proposals in Bangladeshi Taka (BDT) tailored to clear corporate reviews or public tender requirements.
Long-Term Specialized Maintenance Support: Absorption systems require precise fluid chemistry. We provide local, factory-trained technicians to handle annual $LiBr$ solution testing, corrosion inhibitor adjustments, and vacuum pump balancing to maximize your chiller's working life.
Turn your engine exhaust and waste hot water into free central air conditioning. Contact our specialized industrial sales engineering desk in Dhaka today to receive a detailed commercial proposal and technical product data sheets based on your facility's layout configurations.
Corporate Headquarters: Podirdia, Khilbarirtek, Vatera, Dhaka-1212. (Nur-E-Madina Mosjid Complex)
Sales & Project WhatsApp: +8801722039029
Corporate Mailbox: bhaibhaiengineering51@gmail.com
Engineering Platform: https://www.bhaibhaiengineering.com/
Q1: How can engine exhaust create cold water inside an absorption chiller?
Ans: It uses a specialized chemical vacuum process. Inside a deep vacuum chamber, water boils at an ultra-low temperature and absorbs heat from your building's cooling loop. A concentrated Lithium Bromide liquid salt solution absorbs this water vapor, and your factory's hot engine exhaust gas is used to heat and boil the water back out of the salt solution so the cycle can repeat continuously.
Q2: What happens if our factory gas generators are running at low capacity?
Ans: The DMAR-Y features an integrated microprocessor control panel and VFD solution pumps. If your generator output drops, the system automatically slows down its chemical pumps and matches its operations to the available waste heat, maintaining smooth performance even at partial loads.
Q3: Does this chiller require an outdoor cooling tower setup?
Ans: Yes. Because an absorption chiller must dissipate heat from both its internal refrigeration cycle and the high-temperature exhaust input, it requires a steady outdoor cooling tower loop to manage the thermal load.
Q4: What special maintenance does an exhaust absorption chiller require?
Ans: Since there are no large moving mechanical compressors, wear and tear is very low. Maintenance focus shifts to keeping the internal vacuum tight via the auto-purge system, running annual chemical tests on the Lithium Bromide solution to check corrosion inhibitor levels, and inspecting the exhaust gas heat exchanger tubes for carbon buildup.
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.
Stay updated with the latest events and industry collaborations from Bhai Bhai Engineering. As leaders in MEP services, we actively participate in trade shows, seminars, and workshops to enhance our expertise and bring innovative solutions to the field. Discover our role in shaping the future of MEP design, installation, and maintenance services.
