Description
Honeywell MARD-12 12″ Round Zone Damper Overview
The Honeywell MARD-12 is a 12-inch round zone damper engineered for precision airflow control in residential and light commercial HVAC zoning systems. Featuring a 24Vac power open/power closed design with a three-wire floating actuator, this damper delivers dependable, active control in both directions — ensuring accurate positioning and responsive performance across all operating conditions.
Power Open / Power Closed Operation
Unlike spring-return dampers, the MARD-12 uses a true power open/power closed (floating) actuator. This means the damper is actively driven to both the open and closed positions using 24Vac control signals, providing positive shut-off and precise modulation without relying on a spring mechanism. This design is ideal for zoning applications where consistent airflow management is critical.
Key Features
- 12-inch round duct damper for standard round duct installations
- 24Vac operating voltage — compatible with standard HVAC zone control panels
- Power open / power closed actuation for active bi-directional control
- Three-wire floating actuator for reliable zone panel integration
- Designed for residential and light commercial zoning applications
- Honeywell quality construction for long-lasting, dependable performance
Specifications
- Model: MARD-12
- Duct Size: 12″ Round
- Control Voltage: 24Vac
- Actuation Type: Power Open / Power Closed
- Wiring: Three-Wire Floating
Application
The MARD-12 is ideal for use with zoning control panels and thermostats in forced-air HVAC systems. It installs directly into 12-inch round ductwork and integrates seamlessly with standard 24Vac zone control systems, making it a go-to solution for contractors building or upgrading multi-zone comfort systems.









