New zone control panels are available for residential applications. Model ED3 has a three-zone design, and Model ED4 has a four-zone design. The microprocessor-based panels alternate heating and cooling modes during conflicting equipment calls. The capacity limit check determines whether a second stage is really needed. Features include a purge control to recover residual heating or cooling, dual-fuel compatibility, and single zone override of all other zone settings.
DuroZone, a div. of Duro Dyne Corp., 81 Spence St., Bay Shore, NY 11706; 631-249-9000; www.durodyne.com.