FA6615-R Optical Smoke Alarm – Replaceable Batteries

No – this is a smoke alarm only and does not detect carbon monoxide. For CO protection, install a dedicated carbon monoxide alarm such as the FireAngel FA6829S alongside your smoke alarms. For combined protection in a single unit, consider the FireAngel SCB10-R combination smoke and CO alarm.

Install a smoke alarm on every level of your home. Position one in the hallway and landing on each floor, plus in bedrooms, living rooms, and dining rooms. Mount on the ceiling at least 300mm from any wall or light fitting. Do not fit a smoke alarm in the kitchen, bathroom, or garage – use a dedicated heat alarm such as the FireAngel FA6720-R for those areas instead. See our complete guide to installing smoke, heat and carbon monoxide alarms for step-by-step placement advice.

In England, at least one smoke alarm is required on every storey used as living accommodation under the Smoke and Carbon Monoxide Alarm (England) Regulations 2015 (amended 2022). Scotland and Wales have their own requirements. For whole-home coverage, the FireAngel Pro Connected range wirelessly interlinks all your alarms so if one sounds, they all sound.

Press the large central test button on the FA6615-R. The quiet test function checks the alarm at a lower volume than a full alarm, so testing will not disturb loved ones or neighbours. Test at least once a week and vacuum around the alarm every six months to remove dust. See our full guide to testing your fire alarms for more detail.

A single chirp at regular intervals usually means the battery is running low. On the FA6615-R, the Sleep Easy feature lets you silence low-battery chirps for up to 8 hours while you arrange replacement batteries. Simply swap the two AA batteries for new ones to restore full protection. A continuous loud alarm means smoke has been detected – evacuate immediately and call 999.

Nuisance alarms are often caused by cooking fumes, steam, or dust near the sensor. The FA6615-R uses optical sensing technology designed to reduce false alarms from cooking while still detecting slow-burning fires. If the alarm sounds without cause, press the test button to silence it temporarily. Make sure the alarm is not installed in a kitchen, bathroom, or other high-moisture area, and vacuum the unit regularly to prevent dust build-up.

On the FA6615-R, a red LED flash approximately every 40 seconds confirms the alarm is active and working normally. If the red light flashes more frequently or the alarm sounds, smoke has been detected – evacuate immediately and call 999. If the LED stops flashing entirely, the batteries may need replacing.

Replace your end-of-life ST-625 or ST-622 with the FA6615-R. It offers optical sensing, replaceable AA batteries, Sleep Easy, and a quiet test function. The FA6615-R fits the same baseplate as the ST-625 with a simple swap, or can be installed using the supplied base and screws. It also replaces the ST-620 and ST-750 using the existing baseplate. See our complete installation guide for step-by-step instructions.