by Brianna Crandall — June 5, 2015—SEMCO, a Missouri-based provider of energy-efficient HVAC equipment and IAQ technology, introduced last week the ASCENDANT Series, a conventional cooling and active desiccant dehumidification hybrid system with regeneration input said to be at the heating, ventilation and air-conditioning (HVAC) industry’s lowest cost of installation and operation.
Available in five standard models ranging up to 20,000-cfm, the ASCENDANT Series is engineered especially for hospital operating rooms, archival and dry storage, hotel/condo buildings, and other applications requiring low dew point temperatures and supply air humidity levels as low as 15 grains.
The ASCENDANT design can operate as a partial or dedicated outdoor air system (DOAS), or as a true variable air volume (VAV) unit. Compared to conventional mechanical DX (direct expansion) or chiller systems, ASCENDANT provides up to three times more dehumidification capacity, achieves dew point temperatures as low as 20°F, and uses up to 60 percent less cooling input, says SEMCO.
ASCENDANT allows the building HVAC system to run more efficiently by utilizing higher coil air discharge and central plant suction temperatures, thus it is compliant with ASHRAE 90.1 building energy, ASHRAE 170 ventilation and ASHRAE 62.1 indoor air quality (IAQ) standards, adds the company.
ASCENDANT also operates without the need for exhaust energy recovery, a feature making it ideal for hospital operating rooms, archival storage and other applications requiring 100-percent outdoor air when exhaust air is unavailable, points out SEMCO.
As latent loads are handled mostly by inexpensive hot water, steam, waste heat or direct gas-fired regeneration energy, the ASCENDANT Series is said to be 50 to 75 percent more efficient than conventional DX dehumidifiers using compressors alone.
This energy-saving potential is maximized with SEMCO’s on-board, integrated direct digital control (DDC) that optimizes the system operation to achieve what the company says are the most flexible air temperatures and relative humidity (RH) combination in the industry. The DDC uses customized algorithms and factory-installed sensors for optimal space condition management compared to more traditional approaches.
The ASCENDANT Series offers additional benefits of:
- Project upfront cooling equipment capital costs are greatly reduced due to energy-efficient design;
- Requires up to 60 percent less cooling capacity of conventional DX systems;
- Variable speed supply and regeneration fan drives options are available;
- Single-point electrical package reduces installation costs;
- HEPA or ULPA filtration options can be added to standard ASHRAE-required MERV filtration;
- Suitable as a VAV or DOAS system for passive or active chilled beams;
- Factory testing of all wiring, controls and components for single-source responsibility; and
- Optional exhaust total energy recovery wheel with less than 0.045-percent contaminant cross-contamination.
For more information on the company’s desiccant wheels, chilled beams and ERV products, visit the SEMCO Web site. SEMCO is a Fläkt Woods company.
