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Mains Powered Carbon Monoxide Alarm with Alkaline Back-up Battery - BRK CO850MBXi

Discontinued Product

This product has been discontinued.

alternative product

Mains Powered CO Alarm - Kidde 4MCO

  • Product Lifespan: 7 years
  • Power: 230V mains powered with battery backup
  • Backup Battery: Rechargeable lithium battery
  • Warranty: 7 year warranty
  • Available with LED or digital display
  • Can be interlinked with smoke and heat alarms
  • CE marked and Kitemarked to BS EN 50291-1 (domestic use)
  • Suitable for ceiling installation
  • Also suitable for the 2022 Scottish legislation

£49.67 inc VAT

£41.39 ex VAT

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Product Overview

The CO850MBXi is a mains powered carbon monoxide (CO) alarm, with a 9V alkaline back-up battery to provide power in the event of mains power failure. This alarm can hardwire interlink with up to 12 compatible carbon monoxide alarms for a simultaneous warning and is supplied with a 5 year warranty as standard. Coloured indicators are used to display power, alarm and faults so any problems can be identified quickly.

  • Mains powered carbon monoxide alarm
  • Alkaline back-up battery (supplied)
  • Hardwire interlink with up to 12 devices
  • 5 year manufacturer's warranty
  • Please note that BRK and First Alert are no longer manufacturing new stock for the European Market and while the products may have a 2018/19 manufacturing date they still provide a full 10 year lifespan and full warranty cover from date of purchase
  • Power, alarm and fault indicators
  • Kitemarked to BS EN 50291-1:2010
  • Loud 85dB warning alarm at 1m
  • Combined test and reset button
  • Dimensions (HxWxD): 134x69x60mm
  • Product warranty and life commences from date of purchase

Please Note: Warranty does NOT include battery

Technical Data
Product Code BKCO850MBXI
Alternative Product Codes CO850MBXI
Brand BRK
Back-Up Battery

9V alkaline

Dimensions (HxWxD)


Sound Output



5 years

Weight 0.23kg
Product Datasheets
FAQs (4)
Q. What are the regulations to testing CO detectors? Do I need to use test gas?

There is no legal or BSI requirement to test the CO detectors with a test gas. A weekly check with the test button is fully sufficient if you choose a quality CO detector. The test gas is offered as a 'belts and braces' option.

Q. Do you need an electrician to connect mains powered smoke alarms?

It is necessary that an electrician installs mains powered smoke alarms.

Q. How long do the batteries last in smoke alarms?

The 9V alkaline batteries and AA alkaline batteries generally last 12 to 18 months. Lithium batteries will usually last 5x longer than their alkaline counterparts, achieving around 5 years lifetime. Some lithium cells are also rechargeable, and when used in a mains-powered alarm may last for the entire functional lifespan of the alarm. Newer alarm models may also feature a "sealed" lithium battery. These batteries are specialist components which are designed to not be removed or need replacing by the user, and have been tested by the alarm manufacturer to ensure they last for the lifetime of the alarm.

Please note: the actual lifetime of your batteries depends on how often the alarms are tested or activated, as sounding the alarm draws more power than when the alarms are "waiting" to detect fire. You should also read your alarm's manual to make sure you only use the recommended types and brands of batteries, as failing to follow these instructions may cause the alarm to malfunction, not alerting you in the event of a fire, and might also invalidate the warranty.

Q. Is this CO Detector compliant with all relevant standards to allow me to place it in a tenanted property as I am a landlord?

Yes, this CO alarm has been Kitemarked to EN 50291-1: 2010 and has been awarded a CE mark. It should be installed in line with the manufacturers guidance.

Excellent Warranty

This product is supplied with a 5 year manufacturers warranty as standard

Looking for more information?

If you have any questions or would like more information about this product you can ask one of our specialists.

Direct Telephone 01507 464181