Mains Heat Alarm with Alkaline Battery Backup - Firehawk FHN450BB

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£19.19 inc VAT
£15.99 ex VAT
Product Overview

The FHN450BB mains powered heat alarm from Firehawk is supplied with easy-to-replace AAA alkaline back-up batteries. With Advanced Thermistor Detection to assist with heat detection, the FHN450BB is perfect for kitchens, garages and lofts. A chirp to indicate low batteries can be silenced with the test and hush button for up to 10 hours, ensuring that your household can remain undisturbed during the night while still being alerted in the event of a fire. The Fast-Fix base allows smoke and heat alarms in the same range to be swapped over if needed.

  • Power: 230V mains powered with battery backup
  • Backup: 3 x AAA alkaline batteries (supplied)
  • Warranty: 6 years manufacturer's warranty
  • Hardwire interlink up to 12 FHN450 heat alarms and FHN250 smoke alarms in the same system
  • Advanced Thermistor Detection makes this alarm suitable for the kitchen, garage, loft or workshop
  • Ideal for locations where smoke alarms can be falsely triggered by normal household fumes and vapours
  • Fast-Fix base allows quick installation and swapping of smoke and heat alarms on the same base
  • Push-Fit for additional safety when removing and replacing the alarm head
  • Low backup battery warning chirp can be silenced for up to 10 hours
  • Large test and silence button for easy testing, maintenance and silencing
  • Suitable for installations complying to BS 5839-6 Grade D2
  • UKCA marked, CE marked, and Kitemarked to BS 5446-2: 2003

Please Note: these FHN series alarms are not compatible with the older FH models.


The table below shows all alarms which can interlink via cable with the Firehawk FHN450RB mains powered smoke alarm.

Please Note: these FHN series alarms are not compatible with the older FH models.

Mains-Powered Alarms

Model Description Battery Backup Interlink
FHN250BB Mains Powered Optical Smoke Alarm 3x AAA Alkaline (included) Hardwire
FHN450BB Mains Powered Heat Alarm 3x AAA Alkaline (included) Hardwire
FHN250RB Mains Powered Optical Smoke Alarm 10 Year Sealed Lithium Hardwire
FHN450RB Mains Powered Heat Alarm 10 Year Sealed Lithium Hardwire


Model Description Power Interlink
FHN600Remote Battery Powered Wireless Remote Control 1x CR2025 Coin Cell IR (infrared)

Technical Data
Product Code FIFHN450BB
Alternative Product Codes FH450BB, FHN450BB
Brand Firehawk
Back-Up Battery

3 x AAA alkaline replaceable batteries (included)

Dimensions (HxDia)

69 x 113mm

Heat Alarm Class

A1 heat detection: 54°C to 70°C

Operating Temperature

0°C to 40°C

Power Type

230V mains with battery backup

Relative Humidity

< 85%

Sound Output


Storage Temperature

5°C to 30°C


6 years

Weight 0.18kg
Product Datasheets

Pricing & Availability

Model Stock Price
Product Code: FIFHN450BB-FAP Stock Level:
More than 20 in stock Expected dispatch: 20th May

£19.19 inc VAT

£15.99 ex VAT

Delivery Options

The following delivery options are available on this product.

Standard Delivery

£3.19 inc VAT - Orders will be delivered in 2-3 working days with Evri

Next Working Day Delivery

£6.19 inc VAT - Orders will be delivered the next working day with Evri

For dispatch today order within

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