The Aprilaire 6404 zone control panel accepts the following control expansion panels:
The Aprilaire 6404 - Zone Comfort Control Panel can be used for any type of zoning application from two to twelve zones. The Aprilaire control panel is configurable for single- or multi-stage, heat/cool or heat pump, and is ideal for use in residential or light commercial applications. The Comfort Control panel features multiple staging options for a more flexible and customized system.
Aprilaire 6404 - Zone Comfort Control Panel specifications: