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Kidde Firex KF20R Mains Powered Optical Smoke Alarm with Rechargeable Back-Up Battery

Product Code: KF20R

Customer Rating: 5 stars

Kidde KF20R Mains Optical Smoke Alarm with Rechargeable Back-Up Battery Key Features

  • Mains powered optical type smoke alarm
  • Sealed rechargeable lithium back-up battery
  • Low profile and unobtrusive design
  • Can hard-wire interlink with up to 23 other mains powered Kidde alarms
  • Dust compensation technology and insect screen to reduce false alarms
  • Easily identify the source alarm on an interconnected system with the Alarm memory feature
  • 70% less energy consumption compared to previous Firex alarms
  • Supplied with a dust cover if being installed during building works
  • Supplied with fixings: 2 x screws and rawl plugs
  • Combined test/hush button allows for regular testing of the alarm and silencing false alarms
  • Low battery warning tone which can be silenced for up to 8 hours
  • Tamper-resistant locking device prevents unauthorised removal of the alarm without the use of a tool
  • Certified to BS EN14604:2005 and CE marked
  • 6 year warranty
  • Suitable for installation as part of a BS5839-6: 2019 Grade D1 system
  • Meets the requirements of the 2022 Scottish Legislation for fire alarms in homes

Product Information

The Kidde Firex KF20R is a mains powered optical smoke alarm with a sealed rechargeable lithium back-up battery which is designed to last the full lifespan of the alarm with no need for replacements. The optical sensor is designed for use in escape or circulation routes and areas where there is a danger of ignition of furniture and surroundings producing slow, smouldering fires. Featuring a tamper-proof locking device which prevents unauthorised removal of the alarm without the appropriate tools and is fitted with a foam gasket to prevent the ingress of dust.

The Kidde KF20R can be hard-wire interlinked with up to 23 other Kidde mains powered alarms which will create an interconnected system where if one alarm is activated, all other connected alarms will sound.

The Kidde Firex (KF) series alarms are vastly improved over previous Firex alarms, offering 70% lower energy consumption and an enhanced slimline design.

The Kidde KF20R is BSi certified to BS EN 14604:2005, CE marked and has a warranty period of 6 years.

This alarm is suitable for installation as part of a BS5839-6: 2019 Grade D1 system.

What's Included?

  • 1 x Kidde KF20R Optical Smoke Alarm
  • 1 x Rechargeable Lithium Back-Up Battery (Sealed)
  • 2 x Screws
  • 2 x Rawl plugs
  • 1 x Instruction Manual

Interlink Compatibility

The KF20R can be hard-wire interlinked with the following alarms, up to a maximum of 24 units on one circuit:

Model Number Device Type Type of Interlink
KF10 230v Ionisation Alarm with 9v Battery Hard-wire interlink
KF10LL 230v Ionisation Alarm with Longlife Lithium Battery Hard-wire interlink
KF10R 230v Ionisation Alarm with Rechargeable Lithium Battery Hard-wire interlink
KF20 230v Optical Alarm with 9v Battery Hard-wire interlink
KF20LL 230v Optical Alarm with Longlife Lithium Battery Hard-wire interlink
KF20R 230v Optical Alarm with Rechargeable Lithium Battery Hard-wire interlink
KF30 230v Heat Alarm with 9v Battery Hard-wire interlink
KF30LL 230v Heat Alarm with Longlife Lithium Battery Hard-wire interlink
KF30R 230v Heat Alarm with Rechargeable Lithium Battery Hard-wire interlink
4MCO 230v CO Alarm with Rechargeable Lithium Battery Hard-wire interlink
4MDCO 230v CO Alarm with Digital Display Screen Hard-wire interlink

Technical Details

Manufacturer: Kidde
Product Code: KF20R
Approvals: BS EN 14604:2005
CE Marked
Product Weight: 242g
Sound Output: 85dB alarm at 3 metres
Dimensions: W:127mm H:127mm D:39mm
Power Supply: 230V mains powered
Back-Up Power Supply: Sealed rechargeable lithium battery
Operating Temperature Range: 0ºC to +40ºC
Operating Humidity Range: Up to 93% RH non-condensing
Manufacturer's Warranty Period: 6 years

Customer Reviews

  • from Bangor Rating:5 stars

    easy 'swap' replacement for an existing Firex/Kidde of the same design. Just basically 'plug and go'. But, if you are replacing an LL version [and probably also a 'straight' KF 10/20] you'll probably need to rewire the plug in connector with the one supplied with the rechargeable head as it has 4 wire terminal block as opposed to 3 wire in the LL version

  • from Macclesfield Rating:5 stars

    This is a direct replacement for KF2R, same mounting and connector. Arrived in two days, fitted in minutes!

  • from YORK Rating:5 stars

    Smoke alarms were described well on their web site which helped us select the correct type to replace 2 that were overdue replacement. Arrived on time and easy to install into a hard-wired system.

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