

4098-9751 | Simplex TrueAlarm In-Duct Smoke Sensor Housing with Relay
- Regular price
- $267.00
- Sale price
- $267.00
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Product Description P/N: 4098-9751
Description
The Simplex 4098-9751 is a TrueAlarm in-duct smoke sensor housing designed for use in HVAC air handling systems. It provides a local relay output and supports both two-wire and four-wire configurations, ensuring reliable duct smoke detection in commercial and institutional applications.
Technical Specifications
Condition | New/Never Used Surplus |
Brand | Simplex |
Category | Panel Accessories |
Part Number | 4098-9751 |
Subcategory | Enclosure Accessory/Kit |
Function | TrueAlarm in-duct smoke sensor housing with optional relay |
Compatible Sensors | Simplex 4098-9714 TrueAlarm analog sensor |
Voltage Range | 18–32 VDC |
Alarm Current | 30 mA @ 24 VDC |
Remote LED Current | 0.6 mA |
Contact Rating | 1 A @ 28 VDC (power limited) / 0.5 A @ 120 VAC (non-power limited) |
Operation Modes | 2-wire (no relay) / 4-wire (relay included) |
Operating Temp | 15° to 122°F (-9° to 50°C) |
UL Temp Range | 32° to 100°F (0° to 38°C) |
Humidity Range | 10–90% RH, non-condensing |
Wiring Connections | Terminal blocks for 18–14 AWG |
Mounting | In-duct installation |
Application | HVAC duct smoke detection |
Status | Active / Legacy depending on system |
Weight | 4.00 lbs |
Information About 4098-9751
The 4098-9751 housing is engineered to mount a spot-type TrueAlarm analog sensor directly into an HVAC duct, allowing smoke detection in environments with limited airflow or small duct sizes where traditional sampling tubes are impractical. It is designed to support Simplex model 4098-9714 TrueAlarm sensors and provides relay contacts rated for both DC and AC applications. For four-wire operation, the housing includes a programmable relay powered by the fire alarm system, while in two-wire operation it functions without relay output. Built with durable construction and reliable terminal block connections, the 4098-9751 ensures supervised performance in challenging HVAC installations.
Key Features:
- In-Duct Smoke Detection: Mounts spot-type sensors directly into duct airflow.
- Local Relay Output: Rated 1A @ 28 VDC (power-limited) or 0.5A @ 120 VAC (non-power limited).
- Dual Operation: Supports both 2-wire (no relay) and 4-wire (relay included) modes.
- TrueAlarm Compatibility: Accepts 4098-9714 TrueAlarm analog smoke sensors.
- Wide Operating Range: Functions between 15° and 122°F (-9° to 50°C).
- Humidity Tolerance: Operates in environments up to 90% RH (non-condensing).
- Supervised Wiring: Terminal block connections for 18–14 AWG conductors.
- Remote LED Support: 0.6 mA current draw without affecting alarm current.
- UL Listed: Certified for life safety system integration.
The 4098-9751 delivers the reliability and precision required for effective duct smoke detection in HVAC fire safety applications.
Description
The Simplex 4098-9751 is a TrueAlarm in-duct smoke sensor housing designed for use in HVAC air handling systems. It provides a local relay output and supports both two-wire and four-wire configurations, ensuring reliable duct smoke detection in commercial and institutional applications.
Technical Specifications
Condition | New/Never Used Surplus |
Brand | Simplex |
Category | Panel Accessories |
Part Number | 4098-9751 |
Subcategory | Enclosure Accessory/Kit |
Function | TrueAlarm in-duct smoke sensor housing with optional relay |
Compatible Sensors | Simplex 4098-9714 TrueAlarm analog sensor |
Voltage Range | 18–32 VDC |
Alarm Current | 30 mA @ 24 VDC |
Remote LED Current | 0.6 mA |
Contact Rating | 1 A @ 28 VDC (power limited) / 0.5 A @ 120 VAC (non-power limited) |
Operation Modes | 2-wire (no relay) / 4-wire (relay included) |
Operating Temp | 15° to 122°F (-9° to 50°C) |
UL Temp Range | 32° to 100°F (0° to 38°C) |
Humidity Range | 10–90% RH, non-condensing |
Wiring Connections | Terminal blocks for 18–14 AWG |
Mounting | In-duct installation |
Application | HVAC duct smoke detection |
Status | Active / Legacy depending on system |
Weight | 4.00 lbs |
Information About 4098-9751
The 4098-9751 housing is engineered to mount a spot-type TrueAlarm analog sensor directly into an HVAC duct, allowing smoke detection in environments with limited airflow or small duct sizes where traditional sampling tubes are impractical. It is designed to support Simplex model 4098-9714 TrueAlarm sensors and provides relay contacts rated for both DC and AC applications. For four-wire operation, the housing includes a programmable relay powered by the fire alarm system, while in two-wire operation it functions without relay output. Built with durable construction and reliable terminal block connections, the 4098-9751 ensures supervised performance in challenging HVAC installations.
Key Features:
- In-Duct Smoke Detection: Mounts spot-type sensors directly into duct airflow.
- Local Relay Output: Rated 1A @ 28 VDC (power-limited) or 0.5A @ 120 VAC (non-power limited).
- Dual Operation: Supports both 2-wire (no relay) and 4-wire (relay included) modes.
- TrueAlarm Compatibility: Accepts 4098-9714 TrueAlarm analog smoke sensors.
- Wide Operating Range: Functions between 15° and 122°F (-9° to 50°C).
- Humidity Tolerance: Operates in environments up to 90% RH (non-condensing).
- Supervised Wiring: Terminal block connections for 18–14 AWG conductors.
- Remote LED Support: 0.6 mA current draw without affecting alarm current.
- UL Listed: Certified for life safety system integration.
The 4098-9751 delivers the reliability and precision required for effective duct smoke detection in HVAC fire safety applications.
