Copeland HMX Liquid Desiccant Module

The HMX module achieves ISMRE2 ratings of 8–0 as a standalone DOAS technology. When combined with energy recovery ventilation and other system enhancements, complete DOAS configurations can reach ISMRE2 ratings of 13.5. This represents best-in-class dehumidification efficiency compared to conventional HVAC systems rated 4–6, ERV systems rated 6–8 and solid desiccant wheels rated 6–8.

HMX liquid desiccant modules can reduce energy consumption up to 40% compared to conventional HVAC systems.¹ This savings results from single-step cooling and dehumidification that eliminates the energy-wasting overcooling and reheating cycle required by traditional direct expansion systems. Lower compressor lift requirements and optimized air and desiccant flow further contribute to energy efficiency.

No. The HMX liquid desiccant module operates as a closed-loop system and does not require an external water source. The liquid desiccant circulates continuously between conditioning and regeneration cycles without requiring additional water. This design simplifies installation and reduces ongoing operational requirements compared to some competing dehumidification technologies.

The HMX module requires minimal maintenance beyond occasional filter changes. The closed-loop design prevents desiccant exposure to the airstream and ductwork, eliminating the need for desiccant servicing or module replacement under normal operating conditions. This reduces maintenance burden and long-term service costs.

Yes. Lithium chloride (LiCl) is nontoxic to humans and safe to animals in normal concentrations. The HMX closed-loop design ensures LiCl never contacts the airstream, ductwork or occupied spaces. This eliminates exposure risks and prevents the corrosion that can occur when LiCl contacts metal surfaces in open-loop systems. Handling during installation requires only basic personal protective equipment such as gloves and eyewear.

Yes. The modular design allows OEMs to add or remove individual HMX modules to match specific dehumidification capacity and cooling loads. This configuration flexibility enables precise system sizing for diverse applications, from small commercial buildings to large facilities with high ventilation requirements. The ability to scale capacity helps optimize both performance and installed cost.

The HMX membrane technology separates liquid desiccant from the airstream through a physical barrier. Outdoor air passes over one side of the membrane while desiccant flows through the opposite side in a completely sealed circuit. Moisture transfers through the membrane without any mixing of supply air, exhaust air or desiccant. This design ensures superior indoor air quality compared to systems that mix airstreams.

Copeland offers pre-engineered subsystems, including the desiccant conditioner (modules, piping, valves, tanks and pumps for supply air conditioning), desiccant regenerator (components for desiccant regeneration) and chiller subsystem (compressors, pumps and heat exchangers for thermal management). These subsystems reduce OEM engineering time and streamline integration into packaged DOAS units.

Yes. The desiccant regeneration subsystem can be programmed to operate during off-peak hours when energy costs are lower. The desiccant effectively acts as an energy storage medium, absorbing moisture during peak daytime hours and regenerating at night. This peak load management capability provides additional energy cost savings in regions with time-of-use utility rates.

HMX module technology is well-suited for commercial buildings requiring high ventilation rates, precise humidity control and superior indoor air quality. Target applications include offices, schools, healthcare facilities, hospitality properties, supermarkets and industrial processing environments. The technology performs particularly well in humid climates and applications with variable moisture loads throughout the year.

Copeland developed HMX technology through rigorous research and development in state-of-the-art HVAC laboratories. The modules have been validated through extensive field trials with leading HVAC OEMs across diverse applications and operating conditions. This validation process ensures reliable performance and confirms the energy savings and dehumidification effectiveness documented in product specifications.

Copeland has been granted 24 patents covering HMX liquid desiccant module technology, with 12 additional patents pending. These innovations reflect significant progress in membrane design, desiccant flow optimization, system integration and control strategies. The U.S. Department of Energy has recognized membrane and liquid desiccant technologies as crucial for improving HVAC sustainability.