Kidde Firex KF20R Optical Smoke Alarm Mains Interlinked with Rechargeable Lithium Battery

The Kidde Firex KF20R Optical Smoke Alarm with Built-in rechargeable Lithium back-up is a high-performance mains-powered smoke detector with battery backup, designed to provide reliable fire detection across domestic properties.

With the ability to interlink up to 23 alarms, the KF20R ensures that when one alarm detects smoke, all connected units sound delivering full-property protection and early warning.

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Kidde Firex KF20R Optical Smoke Alarm Mains Interlinked with Rechargeable Lithium Battery

Interconnectable Mains Smoke Alarm with Built-in rechargeable Lithium back-up for Reliable Whole-Home Protection

The Kidde Firex KF20R Optical Smoke Alarm with Built-in rechargeable Lithium back-up is a high-performance mains-powered smoke detector with battery backup, designed to provide reliable fire detection across domestic properties.

With the ability to interlink up to 23 alarms, the KF20R ensures that when one alarm detects smoke, all connected units sound delivering full-property protection and early warning.

Available now from Alert Electrical your trusted UK supplier of fire safety products since 1996

Features

  • Mains powered smoke alarm (230V)
  • Built-in rechargeable Lithium back-up
  • Interconnectable with up to 23 Firex alarms
  • Optical sensor – ideal for smouldering fires
  • Alarm memory identifies triggering unit
  • Dust compensation & insect-resistant bug screen
  • 85dB alarm sound output
  • Test & hush button for easy operation
  • Tamper-resistant locking feature
  • Auto reset after activation
  • 6 year manufacturer warranty

Interlinked Whole-Home Safety

The KF20R can be connected with up to 23 compatible Kidde Firex alarms (smoke, heat or CO), ensuring:

  • Simultaneous alarm activation throughout the property
  • Early warning in all rooms
  • Improved safety for occupants

Optical Sensor Technology

The optical sensing chamber is designed to detect slow, smouldering fires, such as:

  • Upholstery or furniture fires
  • Electrical overheating
  • Cigarette smoke ignition

Making it ideal for hallways, living rooms and bedrooms.

Reliable Backup Protection

Even in the event of a power cut, the Built-in rechargeable Lithium battery backup ensures continued operation, maintaining protection at all times.

Easy Operation & Maintenance

  • Test/Hush button for quick testing and silencing nuisance alarms
  • Alarm memory function identifies the source alarm
  • Dust compensation technology reduces false alarms
  • Bug screen mesh prevents insect interference

Compliant with UK Regulations

The KF20R is suitable for use in installations requiring compliance with:

  • BS 5839-6 (Grade D)
  • UK Building Regulations for domestic fire detection
  • Model: KF20R
  • Product Type: Optical Smoke Alarm
  • Power Supply: 230V Mains + Built-in rechargeable Lithium Battery Backup
  • Interlinking: Up to 23 units
  • Sensor Type: Optical (Photoelectric)
  • Alarm Output: 85dB at 3 metres
  • Temperature Range: -10°C to +40°C
  • Humidity Range: Up to 93% RH (non-condensing)
  • Dimensions: 127 x 127 x 41mm
  • Weight: 246g (including battery)
  • Warranty: 6 Years

Ideal Locations

  • Hallways and corridors
  • Bedrooms
  • Living rooms
  • Loft spaces (within temperature range)

Note: Not recommended for kitchens – use a heat alarm instead.

Why Buy from Alert Electrical

Alert Electrical supplies trusted fire safety products used by electricians and homeowners across the UK, offering competitive pricing, fast delivery and expert support.

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