--- product_id: 80320779 title: "First Alert CO400 Battery Powered Carbon Monoxide Alarm" brand: "first alert" price: "£41.37" currency: GBP in_stock: true reviews_count: 5 category: "First Alert" url: https://www.desertcart.co.uk/products/80320779-first-alert-co400-battery-powered-carbon-monoxide-alarm store_origin: GB region: United Kingdom --- # 5-year end-of-life timer for peace of mind Electrochemical sensor for top accuracy Battery-powered for flexible placement First Alert CO400 Battery Powered Carbon Monoxide Alarm **Brand:** first alert **Price:** £41.37 **Availability:** ✅ In Stock ## Summary > 🚨 Stay ahead of danger with smart, silent protection! ## Quick Answers - **What is this?** First Alert CO400 Battery Powered Carbon Monoxide Alarm by first alert - **How much does it cost?** £41.37 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.co.uk](https://www.desertcart.co.uk/products/80320779-first-alert-co400-battery-powered-carbon-monoxide-alarm) ## Best For - first alert enthusiasts ## Why This Product - Trusted first alert brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **True Portability:** Battery-powered design means no wiring hassles—install anywhere, anytime. - • **Trusted Protection:** Backed by a 5-year limited warranty from First Alert, a leader in home safety. - • **Unmatched Accuracy:** Electrochemical sensor technology ensures precise CO detection, keeping your space safe. - • **User-Friendly Control:** One-touch silence/test button for effortless operation and quick alerts. - • **Long-Lasting Reliability:** Includes a 5-year end-of-life timer and low battery warning to never leave you unprotected. ## Overview The CO400 Battery Powered Carbon Monoxide Alarm by First Alert features an advanced electrochemical sensor for the most accurate CO detection. Its battery-powered design offers flexible installation without wiring, complemented by a simple silence/test button, low battery alerts, and a 5-year end-of-life timer. Compact and reliable, it comes with a 5-year limited warranty, ensuring your home stays safe and sound. ## Description From the manufacturer First Alert CO400 Battery Powered Carbon Monoxide Alarm Battery Powered 1-9V Battery (included) power source. (NOTE: Product may come with 2 AA batteries. This is the same model). Test/Silence This alarm comes equipped with a mute button that serves the dual purpose of quickly silencing your alarm as well as testing its function. Electrochemical Sensor This alarm utilizes an Electrochemical Sensor that allows for optimal efficiency in detecting carbon monoxide. 85dB Alarm 85db sound output further establishes the ultimate in peace of mind. End of Life Timer also lets you know it's time to replace. Review: Saved my life - Installed as soon as they arrived to replace older models that the batteries had expired in (7 year batteries and no maintenance or replacement option). These do have batteries that have to be or can be replaced. The 2nd night after installation, the detector I had mounted in my bedroom (installed all 6 throughout my house) went off around 2:00 AM and awakened me. I immediately shut my gas furnace down and called a HVAC company. They found a crack in my heat exchanger as well as issue with the flue or exhaust pipe that was allowing CO to enter my home. Had I not replaced my CO detectors when I did, I wouldn't be writing this review now. Well worth my investment!! Easy installation and had all 6 up and operating in less than 30 minutes as well as reasonably priced. Purchased this pack of 6 for less that the other 2 I had bought 7 years ago. Review: Excellent and easy to install - I purchased this alarm to install in the upstairs hallway between bedrooms. It was very easy to install and works perfectly and provides the added security I required. I was surprised and happy at how quickly the parcel arrived! ## Features - Battery-operated carbon monoxide alarm - Uses electrochemical carbon monoxide sensor--the most accurate technology available - Simple to use silence/test button, low battery warning, end-of-life timer - 1-9V Battery (included) power source. (NOTE: Product may come with 2 AA batteries. This is the same model.) - 5 year limited warranty - Package Contents: 1 Piece Powered Carbon Monoxide Alarm ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B000N8OYXI | | Alarm | Audible | | Best Sellers Rank | #13,011 in Home Improvement ( See Top 100 in Home Improvement ) #18 in Home Security Alarms | | Brand | First Alert | | Built-In Media | 1 Piece Powered Carbon Monoxide Alarm | | Colour | White | | Customer Reviews | 4.6 out of 5 stars 16,892 Reviews | | Enclosure Material | Multi | | Global Trade Identification Number | 00029054000699 | | Item Dimensions D x W x H | 2.5D x 12.7W x 7.6H Centimeters | | Item Type Name | First Alert CO400FF Battery Powered Carbon Monoxide Alarm | | Item Weight | 0.45 Pounds | | Manufacturer | Jarden Safety | | Manufacturer Warranty Description | 5 year warranty | | Mfr Part Number | CO400 | | Model Number | CO400 | | Number of Items | 1 | | Operating Humidity | 10-95% RH | | Power Source | Battery Powered | | Product Dimensions | 2.5D x 12.7W x 7.6H Centimeters | | Product Style | Simple | | Sensor Type | Electrochemical | | Style | Simple | | UPC | 029054000699 | | Unit Count | 1.0 Count | ## Product Details - **Brand:** First Alert - **Style:** Simple - **Power Source:** Battery Powered - **Colour:** White - **Product Dimensions:** 2.5D x 12.7W x 7.6H Centimeters - **Item Weight:** 0.45 Pounds - **Alarm:** Audible - **Operating Humidity:** 10-95% RH - **Sensor Type:** Electrochemical - **Global Trade Identification Number:** 00029054000699 ## Images ![First Alert CO400 Battery Powered Carbon Monoxide Alarm - Image 1](https://m.media-amazon.com/images/I/51RBX7hitxL.jpg) ![First Alert CO400 Battery Powered Carbon Monoxide Alarm - Image 2](https://m.media-amazon.com/images/I/71hAwlBG2vL.jpg) ![First Alert CO400 Battery Powered Carbon Monoxide Alarm - Image 3](https://m.media-amazon.com/images/I/61iNBAMSOZL.jpg) ![First Alert CO400 Battery Powered Carbon Monoxide Alarm - Image 4](https://m.media-amazon.com/images/I/61JZgbyiECL.jpg) ![First Alert CO400 Battery Powered Carbon Monoxide Alarm - Image 5](https://m.media-amazon.com/images/I/61gHs4yM9gL.jpg) ## Questions & Answers **Q: Can this detect LPG gas leak ?** A: Carbon monoxide is a very different gas to natural gas, often created when fuel is burned in the presence of low levels of oxygen. As carbon monoxide is an entirely different composition to natural gas, carbon monoxide detectors will not detect natural gas leaks. ## Customer Reviews ### ⭐⭐⭐⭐⭐ Saved my life *by G***R on 2 December 2016* Installed as soon as they arrived to replace older models that the batteries had expired in (7 year batteries and no maintenance or replacement option). These do have batteries that have to be or can be replaced. The 2nd night after installation, the detector I had mounted in my bedroom (installed all 6 throughout my house) went off around 2:00 AM and awakened me. I immediately shut my gas furnace down and called a HVAC company. They found a crack in my heat exchanger as well as issue with the flue or exhaust pipe that was allowing CO to enter my home. Had I not replaced my CO detectors when I did, I wouldn't be writing this review now. Well worth my investment!! Easy installation and had all 6 up and operating in less than 30 minutes as well as reasonably priced. Purchased this pack of 6 for less that the other 2 I had bought 7 years ago. ### ⭐⭐⭐⭐⭐ Excellent and easy to install *by A***R on 17 December 2016* I purchased this alarm to install in the upstairs hallway between bedrooms. It was very easy to install and works perfectly and provides the added security I required. I was surprised and happy at how quickly the parcel arrived! ### ⭐⭐⭐⭐⭐ Great price. Mounting moderately challenging. *by M***L on 28 August 2019* Had a false alarm the day after one was installed. Only happened one time. Would be better if the unit had a detachable back like fire alarms do to mount. Had to measure and get the screws in just the right place. The price is half what you’d pay in a store ## Frequently Bought Together - First Alert CO400 Carbon Monoxide (CO) Detector, Battery Operated Alarm, 1-Pack - First Alert CO605 Plug-In Carbon Monoxide Detector with Battery Backup , White - Kidde Carbon Monoxide Detector, Battery Powered CO Alarm with LEDs, Test-Reset Button, Low Battery Indicator, Portable --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.co.uk/products/80320779-first-alert-co400-battery-powered-carbon-monoxide-alarm](https://www.desertcart.co.uk/products/80320779-first-alert-co400-battery-powered-carbon-monoxide-alarm) --- *Product available on Desertcart United Kingdom* *Store origin: GB* *Last updated: 2026-05-27*