Firehawk FHB10-RF Optical Smoke Alarm

The Firehawk FHB10-RF is a battery-powered optical smoke alarm that talks to the other Firehawk RF-Link alarms in your home by radio, so that when one sounds they all sound. It has a sealed-in 10 year lithium battery, an auto switch mounting plate that turns it on when it is clipped to the plate and off when it is removed, and a 10 year warranty¹. For a household getting ready for a power cut, a storm or any night when the mains might fail, that matters: it keeps working when the electricity does not.

What you do with it is simple. Fit one on each level of your home, in hallways, corridors and all escape routes, and within 3 metres of all bedroom doors, and interconnect them all². Then test the system from every alarm, not just one, so you know each unit is genuinely linked³. A red light flashing once a minute is normal: it means the alarm has power⁴.

What the FHB10-RF is and what it does for a household

The maker describes the FHB10-RF as a battery optical multi-criteria-enhanced radio interlinked smoke alarm⁵. In plain terms it is an optical smoke alarm, which means it looks for smoke rather than heat, and it carries a radio transmitter so it can be linked wirelessly to other Firehawk RF-Link devices. The maker lists it as suitable for use as part of a Grade F1 system, which is a system of one or more battery powered detectors run from a tamper proof primary battery⁶.

For an ordinary household the point of the radio link is coverage. A fire that starts in a kitchen or a downstairs cupboard can be sounding an alarm in an upstairs bedroom within seconds, without any wiring between the two. The maker's minimum protection advice is to install at least one smoke alarm on each level of your home, in hallways, corridors and all escape routes, and within 3 metres of all bedroom doors, with all alarms interconnected². That is the layout the radio link is designed to serve.

The alarm also carries the maker's TSE-Technology, which it says provides stability across a range of environmental conditions, reducing nuisance alarms whilst enhancing detection⁴. It has a unique X-Profile detection chamber controlled by bespoke software, and an alarm silence button that the maker describes as ideal in non-emergency situations such as nuisance alarms⁴. Those two features are about the same problem: an alarm that goes off for steam or cooking smoke is an alarm a household learns to ignore, and the maker has built in ways to reduce that without switching the unit off.

It is one of a family. The Firehawk range includes a heat alarm, a carbon monoxide alarm and a hard of hearing alarm, and the FHB10-RF links with all of them³. If you are choosing between alarm types for different rooms, the site's guide to smoke alarms and how to choose one sets out the options, and the comparison of optical or ionisation alarms explains why an optical unit like this one suits escape routes and living areas.

Assembling the alarm and radio base without blocking the antenna

The FHB10-RF comes as two parts that lock together: the alarm head and the radio base, which the maker also calls the pattress. To assemble it, bring the alarm and radio base together and twist or slide to lock into place. The light will flash red and the device will beep when they are locked together³. On Firehawk smoke and heat alarms generally, the maker's instruction is to line up the vertical line on the alarm with the arrow on the base, then twist clockwise; to remove it, press the security tag and twist anti-clockwise⁷.

There is one assembly detail that decides whether the radio link works at all. The maker's manual carries an explicit warning that the wire can interfere with the radio's antenna if it is not secured in the retaining slot³. In other words, the linking range and reliability depend on that wire being tucked where it belongs, not left loose across the aerial. If you are assembling several alarms, check this on each one before you close the unit up.

Once assembled, the unit behaves in a particular way at the plate. The FHB10-RF uses an auto switch mounting plate: power is automatically switched on when the alarm is attached to its mounting plate and off when it is removed⁴. That is convenient, because there is no separate switch to forget, but it has a consequence you should know about. An alarm that is off its plate is off, and it will not detect smoke. FireAngel makes the same point about its own battery powered alarms, warning that removing the smoke alarm from its base plate will deactivate the unit and prevent it from detecting smoke⁸. Treat a Firehawk alarm sitting on a table, waiting to be fitted, as not protecting anyone.

Linking your alarms: press test, wait for the beep

Linking is the step that turns a set of individual alarms into a system. The maker's procedure is short. Press the test button on any assembled alarm, which puts it into linking mode and makes its light flash red and green³. Then wait a few seconds for the alarm to beep and stop flashing its lights; at that point the alarm is linked³. Repeat for each alarm you want in the system, up to the maker's maximum of 20 x RF-Link alarms⁵.

The maker's pairing guide for the wider RF-Link range gives the same sequence in the same words, which is reassuring if you are linking a mixture of Firehawk devices: bring the alarm and radio base together and lock them, wait a few seconds for the beep and for the lights to stop flashing, and the alarm is linked⁹. The guide also says to perform a test from each alarm in the system to ensure every alarm is successfully linked⁹.

If you are adding a new alarm to a system that is already running, the route is slightly different. Open any already linked alarm and press the white RF button on the radio pattress to enter linking mode; the red and green LED will flash³. The same button starts the reset procedure described below³. Once you have finished, leave linking mode by waiting 20 seconds or pressing the test button on the first alarm³.

Testing the system from every alarm

Testing is where a linked system earns its keep, and it is the step most households get wrong. The maker's instruction is to press the test button on any one alarm and wait for each linked alarm to sound, then to perform a test from each alarm in the system to ensure every alarm is successfully linked³. The reason for testing from every unit is that a test from one alarm proves the others receive from that one; it does not prove that every alarm can transmit. Testing each in turn checks both directions.

How often? The fire and rescue service advice is to make sure you test the alarm every week¹⁰. The alarm maker Aico advises testing all alarms once a month and ensuring all interconnected alarms sound¹¹. Those two figures differ, and both are in circulation: weekly from the fire service, monthly from the manufacturer. Testing weekly satisfies both, and on a linked system the weekly test is quick, because pressing one button should set off every alarm in the house.

A few things go wrong at this stage, and the maker's troubleshooting guide names them:

• One beep every 11 seconds means the test button is jammed².
• A double beep every minute is the maker's fault warning².
• The test button light stays steadily on or off, rather than flashing about once every minute when the unit is not in alarm, which the troubleshooting guide lists as a fault indicator¹².

If any of those appear, deal with them before you rely on the alarm. A unit with a jammed test button cannot be tested, and an untested unit in a linked system is a gap you cannot see.

What the lights and beeps mean

Most of the questions households ask about this alarm are about a light or a sound, and the maker's answers are consistent across its product pages. The red LED flashes once a minute to indicate power, and flashes constantly to indicate an alarm condition⁴. So a slow red blink is good news: the unit is powered and watching. A rapid, constant red flash alongside the sound means it has detected smoke.

The pattress has its own light. When you plug the alarm into the pattress and switch on the radio base, the pattress LED will flash green twice per second³. If it does not, the maker's manual says to complete the reset step³. The reset is done by holding the Link button on the radio pattress until the red and green LED appears, then releasing it so the pattress begins to flash green, then switching the pattress off¹⁴.

The silence button is for nuisance alarms, not for fires. The maker describes it as ideal in non-emergency situations such as nuisance alarms⁴, and the low battery warning can be silenced for up to 10 hours, which the maker says maintains continuous protection during sleeping hours⁴. That overnight silence is a sensible feature: it stops a low battery chirp waking the house at 3am without leaving anyone unprotected until morning. It is not a reason to delay replacing an alarm at the end of its life.

Keeping it ready: battery, mounting plate and replacement

The FHB10-RF is built to be low maintenance. It has a sealed-in 10 year lithium battery⁴, so there is no annual battery change and no moment where the alarm sits on a kitchen worktop waiting for a new cell. The maker describes it as a long life optical smoke alarm with a sealed-in 10 year battery and lists a 10 year warranty¹³. The datasheet gives the same 10 year warranty figure⁵.

That design choice has a trade-off worth understanding. A sealed battery means the whole alarm is replaced at the end of its life rather than the battery alone. The site's comparison of sealed 10 year or replaceable battery alarms sets out the two approaches side by side. For a prepping household, the sealed unit's advantage is that it cannot be left dead because nobody had a spare battery in the drawer; the disadvantage is that you must diarise the replacement date, because nothing will remind you except the alarm's own low battery warning.

The mounting plate does the switching. Power is automatically switched on when the alarm is attached to its mounting plate and off when it is removed⁴. That is why the maker's reset and linking steps involve opening an alarm and pressing a button on the pattress: the plate is the interface between the alarm head and the radio base. It is also why you should never leave an alarm off its plate for long. FireAngel's warning about its own battery alarms applies in spirit: removing the alarm from its base plate will deactivate the unit and prevent it from detecting smoke⁸.

What works with it: RF-Link alarms and Grade F1 systems

The FHB10-RF is one part of a compatible family. The maker lists it as compatible with the Firehawk RF-Link range of smoke alarms (FHB10-RF), heat alarms (FHH10-RF), carbon monoxide alarms (CO10-RF), the RF-Link module for mains alarms (FHN600RF) and the hard of hearing alarm (FHN800HIA)⁴. The manual gives the same list, describing FireHawk RF-Link devices as able to be radio linked wirelessly to smoke alarms, heat alarms, carbon monoxide alarms, RF-Link equipped mains smoke and heat alarms fitted with the FHN600RF module, and hearing impaired control units³.

That compatibility is what makes the system useful in an emergency. A heat alarm in the kitchen, a smoke alarm on the landing and a carbon monoxide alarm by the boiler can all be tied together, so a problem anywhere in the house raises the alarm everywhere. The maker describes its RF-Link range as offering easy setup interconnectivity for all smoke, heat, carbon monoxide and hard of hearing alarms¹⁵. If you are planning a mixed system, the site's guide to interlinked alarms and how linking works explains the principles, and heat alarms: what they do and where they go covers the kitchen side. For households with a deaf or hard of hearing occupant, smoke and CO alarms for deaf and hard of hearing people explains the warning devices that work alongside an alarm like this one.

The maker also lists the FHB10-RF as suitable for use as part of a Grade F1 system⁶. The site's guide to alarm standards, BS 5839-6 and system grades explains what the grades mean for a home. If you are weighing up whether to go battery or mains, the comparison of battery or mains smoke alarms and of wireless or wired interlinked alarms cover the trade-offs, and the Firehawk brand page lists the rest of the range.

Where it fits a household emergency plan

A smoke alarm is the one piece of emergency kit that earns its place every single night, and the FHB10-RF is built for the nights when the mains does not. Because it runs on its own sealed battery and links by radio, a power cut, a tripped circuit or a flooded consumer unit does not take it out of service. That is the prepping case for it: it is protection that survives the emergency rather than depending on the supply.

The fire and rescue service position is blunt about why it matters. Staffordshire Fire and Rescue Service advises householders to make sure they test the alarm every week¹⁰, and Electrical Safety First reports the case of an Ipswich man who escaped a blaze with his family thanks to a life saving smoke alarm, with experts urging residents to test theirs and to replace batteries when needed¹⁶. A working alarm buys the minutes that get a household out.

To keep the FHB10-RF ready:

• Test the system from every alarm, weekly if you follow fire service advice, monthly at minimum on the maker's guidance¹⁰.
• Check the red light is flashing once a minute on each unit, which shows it has power⁴.
• Keep the alarm on its mounting plate, because off the plate it is switched off⁴.
• Note the fitting date, so the 10 year life and 10 year warranty are not forgotten¹³.
• Link any new alarm to the existing system and test from every unit afterwards³.

If you have a fire at home, the site's guide to what to do if a fire starts in your house sets out the order of actions, and how to make a fire escape plan is the preparation that turns an alarm sounding into a safe exit. For a flat, what to do if there is a fire in your block of flats covers the different decisions. The fire safety checklist for your home and the bedtime fire safety checks are the routines that keep an alarm system working between tests. If you are unsure how often to test, how often to test smoke and CO alarms goes through the intervals, and why does my smoke alarm keep chirping deals with the noises that are not a fire.