Real Question…
what’s the point of hard wiring a smoke alarm if they’re still gonna require a backup battery, which always go dead in the middle of the night & wakes up the whole house.
WTF! ...
The point is that the alarm is wired so it won’t depend on a battery while there is electricity. The battery is a backup in case the fire causes a electricity outage or if there is a fire during an electricity outage.
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