All air-to-air heat exchangers require an outdoor airflow path to facilitate heat removal from the interior of a cabinet. Heat exchangers would have significantly reduced capacity without this outdoor airflow. Therefore the outdoor airflow path is critical and typically the outdoor airflow path is designed to allow maximum airflow to facilitate the greatest amount of heat transfer. Of course the outdoor airflow requires openings in the heat exchanger enclosure and these openings not only allow airflow to pass freely, but also water. Resultantly, manufacturers and users of exterior use heat exchangers have struggled for years with the problem of water infiltration, as these openings allow the free passage of water. With water entering the outdoor airflow path of the heat exchanger, the opportunity exists for water to infiltrate through any minor air leaks within the heat exchanger. This infiltration may be a result of poor design and/or construction, or possibly due to inadequate maintenance.
VoltAire Systems recognized this industry problem during the conceptual design process and focused on designing a solution to significantly reduce the amount of water entering the outdoor airflow path. It was clear that VoltAire’s design needed to create an indirect airflow path that allows air to pass freely with little restriction (and thus little or no reduction in capacity), while significantly restricting water passage. VoltAire’s engineers proceeded with the design process with the main challenge being how to manufacture a cost effective and compact solution while having little or no impact on unit capacity.
As a result of the design and testing process, VoltAire is proud to introduce the Patent Pending Rain Guard Deflector. VoltAire’s design incorporates two key design components. The first component is an aluminum mesh deflector that creates an indirect airflow path that has practically no impact on airflow, while being successful in knocking down rainwater falling and/or blowing through the outdoor airflow opening. The second component of the design is the cover of the heat exchanger that incorporates a water channel that allows water knocked down by the deflector to fall and drain out of the side of the heat exchanger cover rather than allowing the water to enter the heat exchanger. This drainage pattern is achieved with a physical barrier plus a gap between the cover/deflector and front panel of the heat exchanger.
VoltAire’s testing of the Rain Guard Deflector under UL Type 4 testing conditions resulted in an approximate 95% reduction of water entering the heat exchanger’s outdoor airflow path. Most importantly, the design resulted in no reduction in capacity allowing for heat exchanger sizes commonly utilized in the industry. And best yet, the design used simple components with very minimal cost. Therefore the Rain Guard Deflector met the goals of VoltAire’s design team and we are excited to have this cost effective solution available to customers to address the industry’s ongoing challenge.