Duct Smoke Detector Installation Requirements

Refer to the applicable figures below depending on your duct housing model number.

Duct smoke detector installation requirements.

Duct smoke detection nfpa 90a code requirements there are exceptions to the two basic 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. Smoke alarms should be installed at least 10 feet 3 meters from a cooking appliance to minimize false alarms when cooking. Refer to nfpa 90a 72 and 101 for more information.

2 6 p n 3101210 rev 02 iss 28jan13. To ensure correct operation install the duct detector using the following guidelines. Ventilation fan systems used to remove air from the inside of the building to the outside of the building. The local authority having jurisdiction should be consulted prior to the installation of the damper and smoke detector.

If the duct system is designed to carry more than 2000 cfm 5 tons nominal of air you need one in the. Duct smoke detectors alarms and the code. Return air smoke detectors are not required when there is a protection of. With all wiring in place install the detector head.

For proper air sampling duct pressure should be a minimum of 0 01 inches of water. A duct smoke detector should shut off a typical blower and fresh air and turn on the exhaust. Mount smoke alarms high on walls or ceilings remember smoke rises. Duct widths from 6 inches to 12 feet can be accommodated.

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. At these locations air flow is less turbulent and the air smoke mixture should be more homogenous. Install the duct smoke detector on a flat section of hvac duct between six and ten duct widths from any bends or obstructions.

With power source de energized and the smoke detector not installed wire all connections per engineering drawings. 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.