Simplex (4098-9687) Stand Alone Duct Detector 0631142

The Simplex 4098-9687 is a stand-alone duct smoke detector housing. Specifically, it samples airflow inside HVAC ducts and signals on detected smoke. As a result, you get automatic damper control or air-handler shutdown without the need for a fire alarm panel.

The housing carries a 4098-9601 TrueAlarm photoelectric smoke detector. In addition, it provides fail-safe alarm relay contacts on power loss or detector removal.

How the Simplex 4098-9687 Operates

First, duct air enters the housing through the inlet tube. Then, it passes the photoelectric sensing chamber. As a result, smoke present in the airstream triggers the alarm condition.

The alarm condition transfers the on-board SPDT (Form C) relay contacts. Therefore, downstream equipment such as fan starters and damper actuators respond automatically. Furthermore, when the 4098-9842 Duct Control Station (sold separately) is connected, the alarm LED illuminates and a local audible sounder activates.

Important — This is NOT a Fire Alarm Replacement

Per Simplex installation instruction 574-777, the 4098-9687 is intended for HVAC control only. Specifically, it controls dampers and air-handling equipment on detected smoke. However, the installation instructions and NFPA 90A are explicit: “DO NOT CONNECT THE STAND ALONE DUCT DETECTOR TO A FIRE ALARM CONTROL PANEL.” Furthermore, duct smoke detectors must not be used as substitutes for open-area fire protection.

Key Features

• Stand-alone HVAC duct smoke detection — no FACP required
• 4098-9601 TrueAlarm photoelectric smoke detector head included
• SPDT (Form C) dry-contact alarm relay output
• Fail-safe operation — alarm contacts transfer on power loss or detector removal
• Multi-voltage input: 120 VAC, 24 VAC, or 24 VDC
• Two 3/4″ conduit entries (one with included cap plug)
• Magnetic test feature with sensitivity feedback (Normal / More Sensitive / Less Sensitive / Non-Functional)
• Test/Reset and Silence switches available via the 4098-9842 Duct Control Station
• Lightweight 1.4 lb housing for easy handling during installation

Specifications

• Internal detector: Simplex 4098-9601 TrueAlarm photoelectric
• Operating air velocity: 300 to 4,000 ft/min (91 to 1,220 m/min)
• Round duct minimum diameter: 18″ (45.7 cm)
• Rectangular/square duct minimum width: 12″ (using inlet tube 2098-9796)
• Maximum duct width supported: 95″ (using inlet tube 2098-9799)
• Field wiring: #12 to #18 AWG
• Max distance to 4098-9842 Duct Control Station: 500 ft
• Alarm relay contacts: SPDT (Form C) — rated 5 A @ 24 VDC/VAC; or 5 A @ 120 VAC resistive (non-power-limited)

Power Operation Options

• 24 VDC: 20.4–32 VDC input. Standby 40 mA, alarm 50 mA.
• 24 VAC: 20.4–32 VAC input. Standby 100 mA, alarm 125 mA.
• 120 VAC: 102–132 VAC, 60 Hz input. Standby 30 mA, alarm 40 mA.

Power sources must originate from a fused power supply listed for fire protective signaling use, or from a FACP power supply.

Required and Recommended Accessories

• 4098-9842 Duct Control Station — required for remote alarm LED, audible sounder, and Test/Reset key switch
• Air sampling (inlet) tube — required, sized to duct width. Tube part numbers 2098-9796 / 9804 / 9797 / 9798 / 9799 cover 12″ to 95″ duct widths.
• 553-810 Magnet Tester — for periodic magnetic test of the 4098-9601 head
• 553-673 Smoke Detector Aerosol Tester — for NFPA-required annual sensitivity testing

Order the Simplex 4098-9687

Life Safety Consultants stocks the Simplex 4098-9687 along with the 4098-9842 control station and the matching air-sampling tubes. To confirm tube length for your duct width or place an order, call 1-888-557-0558. Alternatively, email sales@lifesafetycom.com.

For more information, contact the Life Safety Consultants team at (888) 557-0558, or email us at: sales@lifesafetycom.com