Do Kidde hard wired smoke alarms have batteries?
The Kidde i12040A is an AC/DC powered, ionization smoke alarm that operates on a 120V power source with 9V battery backup. This alarm uses ionization sensing technology.
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Technical Specifications..
How do you stop a hardwired Kidde smoke detector from beeping?
Resetting the Alarm.
Turn off the power to the smoke alarm at the circuit breaker..
Remove the smoke alarm from the mounting bracket and disconnect the power..
Remove the battery..
Press and hold the test button for at least 15 seconds. ... .
Reconnect the power and reinstall the battery..
Do hardwired smoke detectors need batteries changed?
Testing and Changing Your Smoke Alarm Batteries
If your detector is hardwired into your home's electrical system, replace the backup battery at least every 6 months and replace the smoke detector itself at least every 10 years.