Helpful video reference. FireAngel Safety Technology, the UK's leading manufacturer of domestic fire and CO alarms, demonstrates the installation of a mains-powered heat alarm in a kitchen in their official tutorial "FireAngel Heat Alarm Kitchen Installation". FireAngel products are designed to meet BS EN 54-5 and BS 5839-6 requirements.
1. Understand why kitchens need a heat alarm
Smoke alarms work by detecting particles in the air. Kitchens produce particles every time something is cooked. A heat alarm uses a thermistor to detect a rate-of-rise in temperature (around 8 °C per minute) or a fixed upper threshold (typically 58 °C for a Rate of Rise and Fixed Temperature unit).
BS 5839-6:2019 specifically recommends heat alarms for kitchens and cooking areas in domestic dwellings. Do not fit a standard smoke alarm in a kitchen.
2. Choose the right alarm
Grade D, Category LD2 or LD3 coverage is standard for most homes. A Grade D alarm is mains-powered with a standby battery. Battery-only alarms are Grade F — suitable for rented properties where the landlord cannot wire in mains power, but Grade D is always better.
Look for:
- BS EN 54-5 tested, UK kitchens approval marking
- Interlink compatible with your existing smoke alarms — most manufacturers use their own RF or wire interlink system
FireAngel, Aico and Kidde are common UK brands.
3. Confirm the interlink arrangement
In a new installation, a three-core cable (brown, blue, yellow-and-green earth) supplies the alarm, and the yellow-and-green core is used as the interlink wire between units. Every mains-powered alarm in the house should be interlinked so that one trigger sets all alarms off. Battery alarms can sometimes interlink wirelessly.
Do not mix alarm brands unless they are confirmed interlink-compatible.
4. Choose the position
Ceiling mount, at the highest point of the ceiling. Position it away from the cooking hob — at least 300 mm from the nearest cooking appliance according to BS 5839-6 recommendations, and away from ventilation points, windows and external doors where draughts might delay the response. A central ceiling position, clear of direct steam from a kettle, works well for most kitchens.
5. Fit the base plate
Switch off the relevant circuit at the consumer unit. Confirm dead. Knock out the cable entry on the base plate. Thread the cable through and fix the base plate to the ceiling with the screws and wall plugs provided. In a plasterboard ceiling, use hollow-wall fixings rated to support the alarm weight.
6. Wire the alarm
Strip conductors to the length specified by the manufacturer (usually 8--10 mm). Connect brown to Live (L), blue to Neutral (N), and the interlink wire (often the third core of a 3-core-and-earth cable, or a separate twin cable) to the interlink terminal. Green-and-yellow to Earth (E).
If you are wiring to a ceiling rose rather than a direct circuit feed, follow the alarm manufacturer's wiring guide for that configuration — some alarms must be wired to a permanent live, not a switched live.
7. Fit the alarm head and test
Twist the alarm head onto the base plate until it locks. Restore power. Press and hold the test button for the duration specified by the manufacturer. The alarm should sound at full volume.
Walk to each other alarm in the house and check they sound too (interlink test). If they do not trigger, the interlink wire is either not connected or not matched between units.
When to call us
Mains-powered heat alarms are straightforward to fit on an existing lighting circuit. The more complex version is fitting them as part of a full interlinked system — smoke in the lounge and hall, heat in the kitchen, CO near the boiler — where getting the interlink wiring right across multiple rooms is the challenge. Richard covers interlinked alarm installations across Sandwich and east Kent, including landlord compliance work for rented properties.
Need fire detection fitted in Sandwich?
Richard installs mains interlinked smoke, heat and CO alarms across east Kent. Landlord compliance certificates available.
Contact Richard