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First Alert SCO501CN-3ST ONELINK Battery Operated Combination Smoke and Carbon Monoxide Alarm with Voice Location

4.4 out of 5 stars 227 customer reviews
| 28 answered questions

Price: $49.99 & FREE Shipping. Details
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  • Mounting/wiring of new detector in current location
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  • Demonstrating proper usage and maintenance

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  • Service provided by a local pro
  • Mounting/wiring of new detector in current location
  • Completing unit test cycle
  • Demonstrating proper usage and maintenance
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Estimate: $57.95
86% positive ratings (14 reviews)
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  • Wireless enabled battery operated combination smoke and carbon monoxide alarm
  • Interconnects with other First Alert ONELINK enabled alarms to create a wireless safety network
  • Exclusive voice alarm with up to eleven programmable locations to tell you where potential danger exists
  • Photoelectric smoke sensing technology and Electrochemical carbon monoxide sensor
  • Includes Test/Silence Button - Low Battery Warning - End of Life Timer and 7-year limited warranty
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Frequently Bought Together

  • First Alert SCO501CN-3ST ONELINK Battery Operated Combination Smoke and Carbon Monoxide Alarm with Voice Location
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Total price: $141.70
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Color Name: White
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Product Description

Color Name: White

Product Description

First Alert SCO500 Smoke Detector SCO500

If you want to build an integrated smoke and carbon monoxide alarm system, but without the cost and hassle of retrofit wiring in your home, the ONELINK Combination Smoke Alarm and Carbon Monoxide Detector is an ideal choice. This alarm provides ultimate protection from two deadly threats, and it is packed with innovative features that give you precious time in the event of an emergency. And because it is able to wirelessly communicate with other ONELINK alarms, this device can help you create a whole-home safety network.

Keep your entire home safe with a network of ONELINK alarms that communicate with each other wirelessly.

ONELINK's mesh network ensures you'll hear an alarm no matter where you are in the house.

The ONELINK Combination Smoke Alarm and Carbon Monoxide Detector
  • Allows for wireless alarm interconnectivity.
  • Dual smoke and carbon monoxide detection.
  • Loud 85-dB siren plus talking alarm for safety.
  • Photoelectric smoke sensor reduces false alarms.
  • Two 'AA' batteries included.

You'll hear the loud 85-dB siren even when sleeping or showering. View larger.
Faster Notification for Faster Escape
In the event of a fire or carbon monoxide (CO) emergency, every second counts. Unfortunately, traditional battery-operated alarms can often cost you precious time. For example, if a fire starts in your basement while you're asleep upstairs, you may not hear the smoke alarm, and it may take several minutes before the heat and smoke reaches an alarm that's close enough for you to hear its siren.

Thankfully, the ONELINK Combination Smoke Alarm and Carbon Monoxide Detector is designed to provide you the earliest warning in an emergency. When this clever device detects smoke or carbon monoxide, all integrated ONELINK alarms in your home will together, increasing your chances of getting out safely.

Interconnectivity Without the Wires
Until now, alarms that could signal each other were only available in homes with hardwired systems. All ONELINK alarms, however, communicate with each other wirelessly through integrated radio frequency. This means that when one sounds, they all sound, providing a whole-home safety network.

If you already have an existing system of hardwired alarms, but you are looking for an update, simply replace one of the alarms with the ONELINK Combination Smoke Alarm and Carbon Monoxide Detector--your alarms will continue to be able to communicate with one another.

Talking Alarm Tells You Where the Danger Is
Not only do ONELINK wireless alarms talk to each other, but they also talk to you! Voice warning with location technology means that integrated ONELINK alarms will tell you where the danger is in your home with an actual programmable voice. For example, if there is fire in your basement, the alarm in your bedroom will speak 'Warning, evacuate. Smoke in basement." This feature will help you plan your escape method, so you can evacuate your family as safely as possible.

Accurate Technology Minimizes False Alarms
Utilizing photoelectric technology to sense smoke, the ONELINK Combination Smoke Alarm and Carbon Monoxide Detector reduces the chance of false alarms caused by cooking or bathing.

Additionally, this alarm features an electrochemical CO sensor, which is the most accurate technology available for detecting CO.

Designed for Safety and Ease of Use
As user-friendly as it is effective, the ONELINK has a dual-purpose button that silences the alarm and tests the system's function. And because the device emits a loud 85-dB siren, you'll be sure to hear it, even if you're asleep or in the shower. The audible low-battery signal can be muted for up to eight hours (so as not to disturb your sleep).

As safe as it is easy to use, this ONELINK device is FCC compliant for wireless device standards, and it meets UL217 and UL2034 standards for combination CO and smoke alarms.

The ONELINK Combination Smoke Alarm and Carbon Monoxide Detector is backed by a five-year limited warranty.

What's in the Box
Combination Smoke Alarm and Carbon Monoxide Detector; two 'AA' batteries; and manual.

The First Alert ONELINK provides more features and better protection than standard alarms.

Product Information

Color Name:White

Technical Details

Part Number SCO500
Item Weight 3.2 ounces
Product Dimensions 5 x 5 x 2 inches
Item model number SCO500
Size 1-pack
Color White
Finish White
Material Synthetic
Power Source battery-powered
Voltage 120 volts
Item Package Quantity 1
Number Of Pieces 1
Certification certified frustration-free
Batteries Included? Yes
Batteries Required? Yes
Warranty Description 7 Year

Technical Specification

Additional Information

Customer Reviews
4.4 out of 5 stars 227 customer reviews

4.4 out of 5 stars
Best Sellers Rank #17,572 in Home Improvements (See top 100)
#36 in Home Improvement > Safety & Security > Fire Safety > Combination Smoke & Carbon Monoxide Detectors
#136 in Home Improvement > Safety & Security > Household Sensors & Alarms
#1,399 in Home Improvement > Contractor Supply
Shipping Weight 3.2 ounces (View shipping rates and policies)
Domestic Shipping Item can be shipped within U.S.
International Shipping This item is not eligible for international shipping. Learn More
Date First Available September 14, 2004

Warranty & Support

Product Warranty: For warranty information about this product, please click here [PDF ]


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Customer Reviews

Top Customer Reviews

By K. Cuddeback on November 20, 2007
Color: White Verified Purchase
Pros: Peace of mind connecting basement sensors to attic bedroom, battery life, easy maintenance, easy setup, spoken alarm identifies threat and location and level of Carbon Monoxide at all networked units.

Cons: Price

We have a four-level home. All the carbon monoxide(CO) and fire sources are in the basement or on the first level: A gas furnace, hot water heater, and clothes dryer in the basement, a fireplace on the first floor. We keep the basement door closed and we sleep in bedrooms on the 2nd and 3rd floors, often with doors closed.

Conventional smoke detectors can be fairly hard to hear when that far away and it is also something of a guessing game which one is going off and why.

So two of these units (one for the basement and one for the 2nd floor hallway) address several unique challenges: First, would a detector in the basement ever awake us upper-floor sleepers in time? Second, with a total of 4 detectors in the house, how much time would you waste trying to identify the location and nature of any problem?

While expensive, their cost is the only downside I've experienced in a year and a half of ownership and two of these units are really the best way to install networked CO and fire detectors in a tall house.

These do require setup beyond just putting batteries and mounting, but it was easy considering that each unit must have a spoken location associated with it so that the spoken alarm can explain things like "Warning. Carbon Monoxied detected in Basement" or "Warning. Smoke detected in Hallway".

Note that when one unit detects trouble (or is being tested), the other speaks what the problem is too. Also during tests the unit reports the maximum CO level detected since the last test.
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Color: White
I have 4 of these smoke detectors installed in my cape cod home and it makes me feel safe. When one goes off, they all go off and the deep male voice says whether there is smoke or CO2 in the house. ONCE they went off when there was smoke in the kitchen. The rest of the time they go off, mostly in the middle of the night for some mysterious reason, saying, in the loud man's voice, "Change the batteries in the kitchen smoke detector" or "Change the batteries in the hallway smoke detector" etc etc. I currently have two of them lying on the floor with the battery drawers pulled out which stops the voice and the beep--beep--beep letting me know the batteries, which I had installed maybe 2 or 3 or 4 weeks before, are used up. The detectors are still lying on the floor days later because if I install new batteries then I will be woken up ever sooner by those batteries wearing out. Still I rate with 3 stars because these detectors make me feel safe. What's wrong with this picture? One is in sight laying on the floor as I type this. I use the brand and number of battery recommended by FirstAlert and I do not test the smoke detectors monthly because that would use up the batteries even more quickly.

UPDATE: 10/25/2011 I had tried the suggestion of someone to switch to lithium batteries. He said his batteries lasted several years that way. I got lithium betteries for my 5 detectors. One got used up in 2 days, another in 2 weeks! Today I called First Alert 800-323-9005. A nice man asked for the model # SCO500 and the manufacture date (9/2/2005). He said he knew what the problem was. Those smoke detectors drained the batteries too fast (uh, no kidding!) and they were recalled in 2006!! How was I supposed to know that?
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6 Comments 103 people found this helpful. Was this review helpful to you? Yes No Sending feedback...
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Color: White Verified Purchase
Smoke and Carbon Monoxide detectors/alarms are extremely important for every home. People hate to spend the money on them, especially the higher quality (more expensive) detectors, and yet your very life can depend on them. There are many choices on the market today, ranging from cheap, basic models to extremely expensive, high-tech devices. There are two main types of smoke detectors: ionization detectors and photoelectric detectors. Most detectors utilize either one or the other of these technologies while some use both. Most detectors just use a beep-style audible alarm, while some talk, some have strobe lights, and some have a bright light to illuminate a dark area. Many detectors today are combining a smoke and carbon monoxide sensor, so you have dual protection in a single device. You can choose between AC and battery operated devices. Most (if not all) new homes are built with AC detectors in all of the vital areas, which usually contain a battery backup in case of a power outage. Many of these new detectors, installed in new homes, are linked together so that one detector will trigger all of them to sound their alarm. This is a very useful feature, since an alarm in the basement may not be heard by sleeping individuals in an upstairs bedroom. However, getting this protection in an existing, older home was almost impossible until a few years ago when manufacturers started utilizing wireless technology to allow communication between multiple detection devices.

My wife and I recently decided to move our bedroom into the basement level of our home. It allowed our three children to all have a room of their own, but we were very concerned about what would happen if there was a fire and we did not hear an alarm go off on the upper level of our home.
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5 Comments 92 people found this helpful. Was this review helpful to you? Yes No Sending feedback...
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