Smoke alarms may chirp at night due to a low battery, or because the alarm is reaching its end of life, which is typically 8-10 years. Smoke alarms can also chirp at night because home temperatures often drop several degrees, which can impact the chemical reactions inside the battery, reducing capacity.
- When the temperature drops, chemical reactions inside a battery slow down, and ions move more slowly through the electrolyte – which is a crucial component within the battery that facilitates the flow of electrical current.
- This slowdown increases internal (ionic) resistance and causes a voltage drop inside the cell – which in turn means lower voltage at the cell terminals, resulting in a chirp.
This reaction is also why a cell phone battery drains faster in colder weather.
Other reasons alarms may chirp can include dust or humidity, such as bathroom steam, interfering with the sensor.
How to Help Prevent Late-Night Smoke Alarm Chirps
To help keep smoke alarms from chirping at night, try these tips:
- Install the alarm away from HVAC vents, kitchens and bathrooms, when possible.
- Check batteries regularly, or use a smart smoke and CO alarm that offers a low-battery app notification reminder.
- Choose alarms with alkaline batteries and well-designed lithium cells, which are often less affected by temperature decreases because their electrolytes and internal layouts minimize this resistance.
Stay informed about your home's fire safety with smoke and carbon monoxide detection from First Alert.