Simplex 4098-9751 In-Duct Sensor Housing with Relay
The Simplex 4098-9751 is an in-duct smoke detector housing with an integrated relay. First, it mounts on HVAC ductwork. Then it samples airflow through an inlet tube and returns it through an exhaust tube. As a result, you get continuous air-sampling smoke detection in supply or return ducts.
This housing accepts a Simplex TrueAlarm addressable sensor head (ordered separately). Specifically, the matching head is the 4098-9714 photoelectric sensor.
Integrated Relay for HVAC Control
The 4098-9751 includes a dry-contact relay output. Therefore, it can drive HVAC fan shutdown, damper control, or other duct-related interlocks at the detector location. This is the key difference from the relay-free 4098-9750 model.
Key Features
- Relay output: Dry contact for HVAC shutdown or damper control
- Sampling: Integral inlet and exhaust sampling tubes for duct airflow
- Sensor head: Accepts Simplex TrueAlarm addressable heads (sold separately)
- Loop interface: IDNet / MAPNET II addressable communication
- Application: Duct smoke detection per NFPA 72 and NFPA 90A
Compatible Panels
The 4098-9751 works with Simplex intelligent panels that support IDNet or MAPNET II addressable SLCs. For example, this includes the 4100, 4100U, 4100ES, 4010, 4010ES, and 4020 series panels. However, conventional Simplex panels do not support TrueAlarm addressable duct housings.
Important — Sensor Head Required
The 4098-9751 housing ships without a sensor head. Therefore, also order the matching 4098-9714 photoelectric sensor head separately. In addition, you may need duct sampling tubes sized to your duct width.
Order from Life Safety Consultants
Life Safety Consultants stocks the Simplex 4098-9751 along with matching sensor heads and accessories. As a result, you can complete a duct detection installation from a single supplier. Our team can also confirm panel compatibility before you order.
For more information, contact the Life Safety Consultants team at (888) 557-0558, or email us at: sales@lifesafetycom.com
Additional information
| Weight | 4 lbs |
|---|---|
| Dimensions | 13 × 11 × 7 in |
| Manufacturers | Simplex |
| Compatible Panels | 4100ES,4020,4010,4008 |
| Compatible Bases | Standard TrueAlarm addressable sensor heads |
| Cross Reference | 4098-9751 |
| Relay | Dry contact HVAC shutdown, Sampling: Integral sampling tubes, Head: TrueAlarm addressable, Loop: IDNet/MAPNET II, Application: Duct smoke detection NFPA 72 NFPA 90A |








