System Sensor CO1224TR Carbon Monoxide Detector, 12/24V, 4-Wire, RealTest Technology (Round)

The System Sensor CO1224TR is a round, six-wire, 12/24 VDC system-monitored carbon monoxide detector with RealTest technology, an 85 dBA audible alarm, and a 10-year end-of-life timer. Designed for integration with compatible fire alarm and security control panels, it features an electrochemical CO sensing cell, separate alarm and trouble relays, and a Temporal 4 evacuation signal. Its 6-inch-diameter, low-profile housing supports wall or ceiling mounting, while the UL 2075 listing and supervised trouble reporting support professional carbon monoxide detection applications.

System Sensor CO1224TR Round 12/24V Carbon Monoxide Detector with RealTest

The System Sensor CO1224TR is a six-wire, system-connected carbon monoxide detector featuring a round housing and advanced electrochemical sensing technology for residential and commercial life safety applications. Part of the System Sensor CO1224 Series, this detector monitors the surrounding air for dangerous concentrations of carbon monoxide (CO), an odorless and colorless gas produced by fuel-burning equipment and incomplete combustion. The CO1224TR operates on 12 or 24 VDC power supplied by a compatible fire alarm or security control panel and provides both local audible warning and relay-based alarm signaling for integration with supervised monitoring systems. Its round, low-profile design offers an alternative to the rectangular CO1224T detector for installations requiring a conventional ceiling-mounted appearance. Suitable applications include residential properties, apartment buildings, assisted living facilities, hotels, and commercial occupancies requiring professionally monitored carbon monoxide detection.

The CO1224TR incorporates RealTest technology, which enables functional testing of the electrochemical CO sensing cell using an approved canned carbon monoxide test agent. Unlike a conventional push-button alarm test that primarily verifies electronic signaling and audible notification, RealTest confirms that carbon monoxide gas can enter the sensing chamber and trigger the detector. Installers activate RealTest by pressing and holding the Test/Hush button for two seconds, causing the green LED to flash once per second before applying the manufacturer's recommended CO test agent. When the detector senses the test gas, it activates its alarm output and audible notification, allowing technicians to verify proper operation at the connected control panel. The detector features a Form C alarm relay and a Form A trouble relay, each rated at 0.5 amp at 30 VDC, providing separate signaling paths for alarm conditions and sensor faults. The trouble relay reports detector failures, supervision problems, and end-of-life conditions to the connected system, supporting the monitoring requirements associated with UL 2075-listed carbon monoxide detection equipment.

The System Sensor CO1224TR operates within a 10 to 33 VDC input range, with nominal 12/24 VDC operation, and draws approximately 20 mA in standby, 40 mA during alarm, and 75 mA during testing. When elevated carbon monoxide levels trigger an alarm, the detector activates an integrated 85 dBA audible sounder measured at 10 feet and flashes its red LED in the ANSI Temporal 4 pattern used for carbon monoxide notification. The green LED flashes once per minute during normal standby operation, while the red LED provides visual indication of alarm and trouble conditions. A built-in Test/Hush button allows temporary silencing of the audible alarm for five minutes when CO concentrations are below 350 parts per million, while visual alarm indication continues. The detector also incorporates a 10-year end-of-life timer that activates trouble signaling when the sensing cell reaches its replacement interval. The unit must be replaced by the date marked beneath its cover, and its CO sensing element is not designed for field replacement.

The CO1224TR features a round housing measuring 6 inches in diameter and approximately 1.3 inches high, designed for ordinary indoor environments with operating temperatures from 32 F to 104 F (0 C to 40 C) and relative humidity from 22% to 90%. Its mounting base supports installation on a standard single-gang electrical box or direct surface mounting to a wall or ceiling, with optional drywall anchors included for applicable installations. The detector accepts 14 to 22 AWG conductors through SEMS-type screw terminals, facilitating secure electrical connections and supervised wiring. It is UL 2075 listed for gas and vapor detectors and sensors and is intended for use with compatible control panels configured to distinguish carbon monoxide alarms from fire and intrusion events. The optional System Sensor CO-PLATE replacement accessory can help cover mounting marks or openings left by previously installed detectors when compatible with the mounting arrangement. Combining electrochemical CO detection, RealTest functional testing, supervised trouble reporting, Temporal 4 audible notification, and a 10-year end-of-life timer, the System Sensor CO1224TR provides a system-integrated carbon monoxide detection solution for professionally installed life safety systems.