How to Remove a Hard-Wired Smoke Detector

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Hard-wired smoke detectors can be one of the best investments a family makes. Connected to a home's electrical system, these units set off all the other connected detectors whenever smoke is present, ensuring every occupant knows about the danger, even if it happens in the middle of the night. But despite their safety features, they can be a little more complicated to remove if you need to renovate an area or replace the detector. Fortunately, all you'll need is a screwdriver and some instructions to get started.

How to Remove a Hard-Wired Smoke Detector
Credit: Highwaystarz-Photography/iStock/GettyImages

Understanding the Wiring

Before you remove a hardwired smoke detector, it can help to learn how it's all connected. There are three wires running from the device, two of which are black and white. Those two wires provide the 120 VAC power the detector needs to operate. A third wire, which is red, connects to the home's electrical system and signals other detectors in the home when smoke is present.

As with any wired device in your home, you should shut off the circuit breaker powering the detector before you start working on it. You should also use a non-contact voltage tester to check the wires before you touch them. To do this, you'll need to turn the detector in a counterclockwise motion to unscrew it from the mounting plate. This will leave the wires exposed for testing.

Removing the Detector

Once you've checked that no power is coming through your wires, disconnect the detector from the wires by pulling the connector and separating the wires from the detector. Set the detector aside. Slightly unscrew the two set screws holding the mount to the ceiling or wall. You can remove the mounting plate by slipping the holes over the screws. Pay close attention to make it easier to add the new mount when you're ready.

You can leave the screws in place for the new mount by screwing them back in. This will allow you to paint over the area if you need to or simply leave the space unfilled until you're ready to add the new detector. Tuck the wires safely up into the hole to make sure they're out of the way in the meantime.

Replacing a hard-wired smoke detector is slightly more difficult than a replacing one that is battery powered. However, it only takes a few extra steps to remove your old detector. With the right tools and a little caution, you can safely dislodge your old detector and leave the space ready to upgrade with a new unit.


Stephanie Faris

Stephanie Faris

Stephanie Faris is a novelist and freelance writer whose work has appeared on the websites of Pacific Standard, the New York Post, the Intuit Small Business Blog, and many others. She is the Simon & Schuster author of eight children’s novels, including the Piper Morgan series.