Resideo by Honeywell Modulating Automatic Round Damper

The Resideo by Honeywell Modulating Automatic Round Damper (MARD series) is a round HVAC duct damper with a 24 VAC floating-control modulating motor. It works as a motorized zone damper or as a bypass damper for forced-air systems. The motor powers the damper open and closed, so it gives smooth, accurate control of airflow in the duct.

Key Features:

• 24V modulating motor with floating control for precise damper positioning
• Power-open and power-close operation for zone or bypass damper control
• Single-blade round design that installs in round ductwork
• Works as a bypass damper when paired with a Static Pressure Control (SPC)
• Works as a zone control damper when connected to a compatible zone control panel
• Side-mounted motor with 3-wire connection
• Motor timing of about 90 seconds from open to closed
• ML6161 replacement motor available for easy serviceability

This damper is designed for light commercial applications and can also be used in residential forced-air systems. It helps balance airflow between zones, relieve excess static pressure, and improve comfort and system efficiency. Resideo manufactures the line under the Honeywell Home brand. It is available in a range of round duct diameters, so you can match the damper to your ductwork.