Low battery · Aico · smoke
Aico: One beep about every 32 seconds with a red or yellow flash at the same time
Low battery on an Ei650: the sealed lithium battery is partly used up and the alarm needs replacing.
- What you see
- One red flash about every 32 seconds
- What you hear
- One chirp about every 32 seconds
If it is sounding a full alarm instead: the maker’s emergency instruction
Smoke alarm
Aico: if the alarms are sounding there may be a fire — evacuate, and if in doubt always assume the fire is real (homeowner FAQ). The Ei650 leaflet: check doors for heat before opening, crawl low under heavy smoke, get out and meet at your prearranged place, call the Fire Brigade from a neighbour’s house or a mobile phone giving your name and address, and never re-enter a burning house.
From Homeowner FAQs — Why is my alarm beeping? and Battery Powered Smoke Alarms Ei650 Series — instruction leaflet (Rev 6).
Carbon monoxide alarm
Aico: a sounding CO alarm means carbon monoxide is likely to be present. Turn off any gas appliances, open windows and doors, and leave the property; ring the emergency number of your gas or fuel supplier; do not go back in until the alarm has stopped.
From Homeowner FAQs — Why is my alarm beeping? and Basic Alarm Fault Finding.
What Aico says to do about this signal
- Replace the whole alarm (check the replace-by date on its side).
- Ei650i only: a press of the test button silences the low-battery beeps for 12 hours, and can be repeated.
From Battery Powered Smoke Alarms Ei650 Series — instruction leaflet (Rev 6). If your alarm’s pattern is not exactly this, check the manual for your model: Aico models do not all use the same signals.
Other Aico signals
Low battery on other brands
The same state sounds and looks different on each make — which is why a chirp pattern cannot be read without the brand.
Sources
Every line on this page comes from Aico’s own documents, read on the date shown. Nothing is taken from third-party code sites or other makes.
- Aico / Ei Electronics: Battery Powered Smoke Alarms Ei650 Series — instruction leaflet (Rev 6) — Ei650, Ei650C, Ei650W, Ei650i. www.aico.co.uk Checked 2026-09-29.
- Aico: Homeowner FAQs — Why is my alarm beeping? — Aico mains and CO alarms, incl. 140RC series (FAQ). www.aico.co.uk Checked 2026-09-29.
- Aico: Basic Alarm Fault Finding — Aico alarms (trade fault-finding page). www.aico.co.uk Checked 2026-09-29.