First Alert CO400

First Alert CO400 Carbon Monoxide (CO) Detector User Manual

Model: CO400 | Brand: First Alert

Уводзіны

The First Alert CO400 Carbon Monoxide (CO) Detector is designed to provide continuous monitoring of carbon monoxide levels in your home, offering early warning of this odorless, colorless, and poisonous gas. Equipped with an advanced electrochemical sensor, this battery-operated alarm ensures protection even during power outages. Its user-friendly design allows for versatile placement, including an optional wall mount.

First Alert CO400 Carbon Monoxide Detector, front view

Фронт view of the First Alert CO400 Carbon Monoxide Detector, showing the test/silence button and First Alert logo.

Важная інфармацыя па бяспецы

Carbon monoxide (CO) is a highly toxic gas that can be produced by any fuel-burning appliance. It is invisible, odorless, and tasteless, making it extremely dangerous. CO alarms are crucial for detecting this poisonous gas and providing early warning to protect your family.

Two children playing on a window seat, with text 'Protect your family with advanced CO detection'

Image illustrating the importance of CO detection for family safety.

Official Product Video: Carbon Monoxide Alarms

Гэта відэа забяспечвае завяршэннеview of First Alert Carbon Monoxide Alarms, including their types, placement recommendations, and essential safety tips. It highlights the importance of early detection and regular testing to ensure home safety.

Настройка

Ўстаноўка акумулятара

The First Alert CO400 operates on a 9V replaceable battery. To install or replace the battery:

  1. Locate the easy-access battery door on the back of the unit.
  2. Адкрыйце батарэйны адсек.
  3. Устаўце новую батарэйку 9 В, сачыце за правільнай палярнасцю (+/-).
  4. Надзейна зачыніце крышку акумулятара.
Back of the First Alert CO400 detector showing the easy access battery door and a 9V battery

Тыл view of the detector, highlighting the battery compartment and included 9V battery.

Размяшчэнне

The CO400 detector is battery-operated, offering flexibility in placement without needing an outlet. It can be placed on a tabletop or mounted on a wall.

  • Рэкамендаванае размяшчэнне: Install carbon monoxide alarms on every level of your home and in every bedroom.
  • Avoid placing the detector in areas with high humidity, extreme temperatures, or near combustion sources.
First Alert CO400 detector mounted on a wall next to a door

The CO400 detector mounted on a wall, demonstrating its battery-operated flexibility.

Diagram showing recommended placement of smoke and CO alarms in a house, including bedrooms, hallway, living room, kitchen, and basement

Diagram illustrating recommended placement of CO alarms throughout a typical home.

Інструкцыя па эксплуатацыі

Звычайная праца

Once the battery is installed, the CO400 will begin monitoring carbon monoxide levels. It is designed to provide continuous protection.

Тэставанне сігналізацыі

Regular testing ensures your alarm is functioning correctly. Use the Test/Silence button to perform a test:

  1. Націсніце і ўтрымлівайце Тэст/Цішыня button located on the front of the unit.
  2. The alarm should sound a loud 85-decibel horn, typically a sequence of 4 beeps, a pause, and then 4 beeps again.
  3. Адпусціце кнопку. Сігналізацыя павінна спыніцца.

If the alarm does not sound during the test, ensure fresh batteries are correctly installed and test again. If it still does not alarm, replace the unit immediately.

Close-up of the First Alert CO400 detector showing the Test & Silence Button

Detail of the Test & Silence button on the CO400 detector.

What to Do if the Alarm Sounds

If your carbon monoxide alarm sounds, it indicates the presence of CO. Follow these critical steps:

  1. Leave Immediately: Move to fresh air outdoors or open doors/windows to ventilate the area.
  2. Call Emergency Services: Once in fresh air, call 911 or your local emergency number.
  3. Do not re-enter the premises until emergency responders have cleared the area and confirmed it is safe.

Тэхнічнае абслугоўванне

Замена батарэі

The CO400 is powered by a 9V battery. An audible and visual low battery signal will alert you when it's time to replace the battery. It is recommended to replace batteries every six months, even if the low battery signal has not yet activated.

Сігнал аб заканчэнні жыцця

The detector is equipped with an end-of-life signal chirp, which indicates when it's time to replace the entire unit. The permanent sensor lasts up to 5 years. For optimal safety, replace your alarm every 5 to 10 years, depending on the manufacturer's instructions and the specific model's lifespan.

First Alert CO400 detector on a wall with text 'End-of-Life Warning Lets You Know When It's Time to Replace'

Visual representation of the end-of-life warning, indicating when to replace the unit.

Уборка

To maintain optimal performance, gently vacuum the alarm cover once a month using the soft brush attachment of your vacuum cleaner. Do not paint the unit.

Ліквідацыю непаладак

Understanding the different alarm signals can help you identify the issue quickly:

СігналСэнсДзеянне
4 beeps and a pauseВыяўлены чадны газEvacuate immediately and call 911.
1 beep every minuteНізкі зарад батарэіЗаменіце батарэю 9 В.
5 beeps every minuteКанец жыццяReplace the entire CO detector unit.

Тэхнічныя характарыстыкі

  • Марка: Першая абвестка
  • мадэль: CO400
  • стыль: Харчаванне ад батарэі
  • Крыніца харчавання: Батарэя 9 В (у камплекце)
  • колер: Белы
  • Памеры прадукту: 1" Г x 5" Ш x 3" У
  • Вага прадмета: 7.2 унцыі
  • Будзільнік: Чутны (85 дБ)
  • Тып датчыка: Электрахімічная
  • сертыфікацыя: UL2034
  • Уключаныя кампаненты: Alarm, Mounting Bracket, User Manual, 9V Battery
First Alert CO400 detector with dimensions labeled: 3.4in height, 1.5in depth, 5in width

Dimensions of the First Alert CO400 Carbon Monoxide Detector.

Гарантыя

The First Alert CO400 Carbon Monoxide Detector comes with a 5-гадовая абмежаваная гарантыя. Please refer to the included user manual for full warranty details and terms.

Падтрымка

For further assistance, technical support, or warranty claims, please contact First Alert customer service:

© 2025 First Alert. Усе правы абаронены.

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