The BRK 790MRL (also known as ) mains powered heat alarm with self-charging lithium back-up battery is Kitemarked to the latest British Standards and has a 5 year manufacturer's warranty. Up to 12 smoke and heat alarms from the BRK 700MRL series can be interlinked (via cable) within a single system, allowing all alarms to activate if one is triggered by fire. The 790MRL is suitable for installing in kitchen areas and garages.
- Power: 230V mains powered with lifetime back-up battery
- Backup Battery: Self-charging lithium battery lasts the lifetime of your alarm - GUARANTEED
- Warranty: 5 year warranty
- Please note that BRK and First Alert are no longer manufacturing new stock for the European Market and while the products may have a 2018/19 manufacturing date they still provide a full 10 year lifespan and full warranty cover from date of purchase
- CE marked and Kitemarked to BS 5446-2: 2003
- Suitable for installations complying to Grade D1
- Detects increases in room temperature
- Ideal for kitchens and garages where a smoke alarm would be unsuitable
- A maximum of 12 alarms from the 700MRL series can be interlinked (via cable)
- An interlinked system provides the earliest warning of fire
- Test button facility
- Easy to install push-fit base plate
- This alarm is also suitable for the updated 2022 Scottish legislation for fire alarms in homes
Please note: this product is not a direct upgrade from the 690MBX heat alarm. Upgrading from a BRK 600MBX series alarm featuring an alkaline battery and twist-on base .
The table below shows all the units that can interlink with the BRK mains powered smoke and heat alarms.
Alarms from the Same Series
||Type of unit
||Type of interlink
||Ionisation Smoke Alarm
||Hard wire interlink
||Optical Smoke Alarm
||Hard wire interlink
||Hard wire interlink
Q. I want to install an interlinked smoke alarm system throughout my home, but what type of smoke alarms do I need in different rooms?
We recommend a heat alarm in the kitchen, optical alarms in living rooms and hallway and ionisation alarms on landings.
Q. Why do your mains powered alarms have batteries?
All our mains powered alarms have a battery backup. Although mains powered alarms without this option do exist (BS5839 part 6 grade E), we regard them as far too dangerous, as a lot of fires are caused by electrical faults leaving the building unprotected against fire if the smoke alarms have no backup battery. With our mains powered alarms you will always be protected.
Q. What is the best way to test my alarm?
We recommend testing alarms by pressing the test button built-in to the unit, as this is designed to simulate the detection of the target stimuli (usually smoke, heat, or CO) at the alarm sensor. You should test your alarms regularly to ensure they are protecting building occupants, preferably every week. For more detailed guidance, check the manual included with your alarm.
Q. How long do smoke alarms last before needing replacement?
It is recommended that smoke alarms are replaced after 10 years. This is because the sensors in the smoke alarms become less sensitive and may not activate when a fire is present.
Q. Do you need an electrician to connect mains powered smoke alarms?
It is necessary that an electrician installs mains powered smoke alarms.
Q. When the test button is pressed on an interlinking smoke alarm will this cause all the other units to go off, too?
Yes, by pressing the test button on one alarm all the units in that family will also be activated. To 'teach' the units which other smoke alarms belong to the same family, the smoke alarms have to be set up together during the installation. This is done by pressing a 'housecoding button' or similar process.
Q. If a false alarm goes off can pressing the hush button on any of the interlinking alarms stop all the units beeping?
No, to stop the alarms from sounding the hush button on the unit that started the process needs to be pushed. Pressing any other unit will just silence that one unit. The unit can be identified by the rapidly flashing red LED.
Q. Can a smoke alarm be fitted with a sticky adhesive pad in a let property?
The sticky pad is suitable for all battery operated smoke alarms. However, we cannot judge if battery alarms are suitable for your let property, as let properties usually require mains powered alarms. There is some advice to this in the governments guides to fire risk assessments. http://www.safelincs.co.uk/Fire-Risk-Assessment/
Also see the LACoRS guide for let properties.
Q. How long do the batteries last in smoke alarms?
The 9V alkaline batteries last 12-18 months. Lithium batteries will usually last 5x longer than their alkaline counterparts, achieving around 5 years lifetime. Some lithium cells are also rechargeable, and when used in a mains-powered alarm may last for the entire functional lifespan of the alarm. Newer alarm models may also feature a "sealed" lithium battery. These batteries are specialist components which are designed to not be removed or need replacing by the user, and have been tested by the alarm manufacturer to ensure they last for the lifetime of the alarm.
Please Note: the actual lifetime of your batteries depends on how often the alarms are tested or activated, as sounding the alarm draws more power than when the alarms are "waiting" to detect fire. You should also read your alarm's manual to make sure you only use the recommended types and brands of batteries, as failing to follow these instructions may cause the alarm to malfunction, not alerting you in the event of a fire, and might also invalidate the warranty.
Q. is there a different alarm sound for optical and heat sensors to tell you the difference in what kind of fire it is?
There is only one alarm sound type when a fire is detected, when interconnected all smoke and heat alarms will sound. However only the triggered alarm will have a rapidly flashing red indicator.
Q. Can the mains powered smoke alarm range be connected to mains power via the lighting circuit?
Yes, hard-wired mains powered alarms can be wired to the unswitched live feed of the nearest frequently used lighting circuit.
Q. What sort of smoke alarm system would I need to install for a HMO?
BS 5839-6 recommends that one or two storey HMOs with an individual floor area of no more than 200sqm (not the total of both floors) should have a Grade D smoke alarm system installed. Grade D refers to mains powered smoke alarms with a back up battery power supply. The alarms can be interlinked either by wire or by radio signal and the system does not require a separate fire alarm panel. For HMOs of 3 storey or higher, a Grade A panel system would need to be installed. This can cover the whole of the building, or can be used just for the communal areas with a separate Grade D system installed for the individual dwellings. For both applications, the level of cover should be a minimum of LD3 (in all escape routes) but this may change according to the fire risk assessment.