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

Kidde Firex Smoke & Heat Alarms
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.
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.
| type | Optical Smoke Alarm | brand | Kidde Firex Smoke & Heat Alarms |
| brand | Kidde Firex Smoke & Heat Alarms | ||
| colour | White |