Duct Smoke Detector Installation Requirements

The international mechanical code imc specifies that if the space is air conditioned and the a c unit is over 2 000 cfm a duct smoke detector is required to be installed in the return air duct.

Duct smoke detector installation requirements.

Smoke alarms should be installed at least 10 feet 3 meters from a cooking appliance to minimize false alarms when cooking. A duct smoke detector should shut off a typical blower and fresh air and turn on the exhaust. The duct detector should when possible be located a minimum of six duct widths downstream from a source of turbulence bends inlets or deflection plates. Refer to nfpa 90a 72 and 101 for more information.

Ventilation fan systems used to remove air from the inside of the building to the outside of the building. For proper air sampling duct pressure should be a minimum of 0 01 inches of water. Install the duct smoke detector on a flat section of hvac duct between six and ten duct widths from any bends or obstructions. Duct smoke detection nfpa 90a code requirements there are exceptions to the two basic requirements.

Wall mounted alarms should be installed not more than 12 inches away from the ceiling to the top of the alarm. Energize the duct detector. With power source de energized and the smoke detector not installed wire all connections per engineering drawings. Detector installation 5 1 verify air flow direction and velocity model d4120 detectors are designed to be used in air handling systems with air velocities of 100 to 4000 feet per minute.

Refer to the applicable figures below depending on your duct housing model number. Return air smoke detectors are not required when there is a protection of. 2 6 p n 3101210 rev 02 iss 28jan13. Duct detectors aren t a replacement for room sensors.

Duct smoke detectors alarms and the code. To ensure correct operation install the duct detector using the following guidelines. Mount smoke alarms high on walls or ceilings remember smoke rises. The local authority having jurisdiction should be consulted prior to the installation of the damper and smoke detector.

Standard location when factory mounted will be on the side opposite the damper actuator. Duct widths from 6 inches to 12 feet can be accommodated.