What is Duct Smoke Detector ?

Introduction to Duct Smoke Detectors

What is it?

Duct smoke detectors are devices that detect smoke in HVAC ductwork and air handling systems. They can be used as part of a building's fire alarm system to quickly detect and alert occupants and authorities of potential fires.

Why we use it?

We use duct smoke detectors to improve occupant safety by detecting smoke in HVAC systems and initiating immediate emergency responses.

How it works?

The detector typically contains a sensing element, such as an ionization chamber or photoelectric sensor, which detects the presence of smoke particles in the air passing through the duct. The device may also have a sampling tube that draws air from the duct into the sensing element for more accurate detection.

Major brands that manufacture it

Some of the major brands that manufacture duct smoke detectors include Honeywell, System Sensor, Siemens, and Notifier.


There are different types of duct smoke detectors, including ionization-based and photoelectric-based models. Some models may also feature additional functions, such as carbon monoxide detection or programmable alarm thresholds.

How do we select it?

When selecting a duct smoke detector, consider factors such as sensitivity, response time, airflow rates, and compatibility with the HVAC system. Also, make sure the detector meets local and national code requirements for smoke detection in HVAC systems.

How to install it?

Duct smoke detectors should be installed in HVAC ductwork downstream of the air handling unit, but before any distribution branches or zones. The detector should be mounted securely to the ductwork using brackets or screws, and the sampling tube should be positioned according to the manufacturer's recommendations.

Wire connections required to receive the signals

The wire connections required to receive the signals from a duct smoke detector may vary depending on the specific device and building automation system. Typically, they will require a power supply connection and a communication signal wire that connects to the building automation system or fire alarm control panel. It's important to refer to the manufacturer's installation instructions for proper wiring connections.

in MEP
What is Duct Smoke Detector ?
Administrator December 22, 2023
Share this post
Sign in to leave a comment

Flow Sensors (for water and other fluids)
Introduction to Flow Sensors