Installing beams in the patient rooms allowed the engineers to use 100% outside air. By combining the active chilled beams with a Dedicated Outdoor Air System (DOAS), the design team was able to reduce the volume of primary air supplied to the space by 30% to 60% when compared to a conventional overhead mixed air system. The lower
amount of required recirculated air and reheat energy resulted in significant operating cost savings. This is particularly relevant to healthcare spaces, where the air system is typically constant volume.
The beam system also greatly reduced the risk of airborne infection, as the return air from multiple spaces was no longer being mixed with the fresh air supply like in a traditional system.
While the facility maintenance team was initially wary about condensation, these concerns were easily addressed by the engineer. Even though this was a retrofit project, the risk of condensation could be minimized by sizing the airside system to meet the latent load and outside air ventilation requirements. As long as the humidity levels are controlled, and the supply water temperature is maintained above the dew point temperature of the space, condensation from a chilled beam is no greater a concern than it is when using a conventional all-air system.
The maintenance team's confidence was further increased by implementing a monitoring strategy that included condensation sensors in areas where beams were being used.
Price manufactures a complete line of maximum security, risk resistant grilles, and this design experience was applied when engineering the active chilled security beam.
The security beam features the same perforated face used on Price maximum security grilles, which prevents patients from hiding contraband or injuring themselves. This alteration caused the security beam to perform slightly different from a standard active beam. However, minor modifications to the airflow and water flow rates enabled the beam to meet the capacity requirements of the space.
The active security beam was developed at Price Research Center North (PRCN) in Winnipeg, Canada, which houses the Price Hydronic Test Chamber, the most advanced radiant testing facility in North America. In addition to facilitating rapid product development, Price uses the chamber to perform mockups of radiant products and chilled beams.
These mock-ups enable Price to publish performance data under a variety of test configurations and conditions.
Beams provide the additional benefit of being easier to clean than most HVAC systems, as the coils only need to be inspected every two to five years.
With this installation, Memorial Hospital and Health Care Center became one of the first hospitals in the United States to employ active beams in patient rooms. In all, beams were installed in approximately 27 patient rooms across the two departments, and the system has been running successfully since May 2012.