Efforts to design for an exhaust air transfer ratio (EATR) of 0% frequently increase energy costs without providing any meaningful improvement in IAQ. In most applications, the optimal EATR selection point for energy recovery wheels is in the range of 2-4% – a rate that balances the tradeoffs between IAQ, energy costs, and installation costs.
Understanding these tradeoffs allows engineers, equipment manufacturers, and building operators the most flexibility to meet building performance objectives over a wide range of operating conditions.
Airxchange® engineer Samantha Alleva presents the tradeoffs in a peer reviewed article published in the November, 2017 issue of ASHRAE Journal.