Duct and Damper Control System

Description and Purpose

Duct and damper controls are used in HVAC systems to direct air flow through air conditioning, heating ducts and ventilation systems.

In larger facilities, common air return ducts recycle air within rooms, routing air from rooms within the facility back into the main HVAC system.

Figure 1: Controlling Ducts

In the event of a fire, air return ducts can route smoke and other toxic fumes throughout the building. Duct and damper control systems control ducts, so that when a fire alarm system activates within a particular room or department, dampers within air return ducts close, containing smoke and toxic fumes in the area where they originated.

Likewise, in Energy Management systems, dampers may be installed inside of ducts that distribute conditioned air into a room or department. When a door or window is open in the room or department, the energy management system can close dampers within ducts to limit distribution of conditioned air into the room.

The fire alarm, intrusion, remote control or panic system can integrate duct control so that in the event of a crisis, the system can close ducts so that air flow is limited. The maximum number of ducts that can be controlled by the system depends on the control panel you choose.


Connections and Considerations

The table below refers to the drawing in Figure 1. If you are using this document on line, click the model number in the table below to see more information.


Model No.


Mounting Options




Relay: Addressable with zone input


I/O Module



V-Plex™ Data Bus


Connects to addressable devices, zone input devices and relay modules.



2-wire, 18 AWG, Fire rated, Non-shielded

Use Genesis 1118 for Non-Fire Applications

This part number is an example. See your building and electrical codes for actual jacketing requirements.


Solving Air Flow Issues

For fire safety reasons, automatic dampers are often installed inside return air ducts. In the event of a fire, the fire alarm system can close dampers that are held open, to reduce the spread of smoke and toxic fumes within the facility. Likewise, in the event of a panic alarm, the panic system can close ducts to contain chemical gas, and biological hazards.