The ZD is a power close and spring open damper. It has a 24-volt motor used to control circulating air in HVAC systems and used when a normally-open damper is required. The ZD is typically used with the TrueZONE and other electronic zoning systems.
Honeywell Dampers
Commercial/Residential
Side Mount
Honeywell Home TrueZONE Residential Damper, Series: ZD Series, 12 in H x 8 in W Size, Rectangle Shape, 24 VAC, 0.32 A, 90 deg Rotation, 30 s Timing, Parallel Blade Action, Power Open/Spring Closed Motor, M1-Power/M6-Common/M4-LED Indication Terminal Electrical Connections, 32 to 120 deg F, Aluminum, Import