Kidde i4618 Firex Hardwire Ionization Smoke Detector with Battery Backup (4 Pack)

I replaced some very old 2003 smoke detectors Firex model 120-1072b that had a different long-back AC connector than the new square design. This new model came with some wiring but I opted for the lazy route and just bought some adapter converters (as pictured) and worked like a charm! I should also note these new detectors do include batteries for a backup power source. Took 30 minutes to replace 4, but I also have 20 foot ceilings.

Product was fine but the listing did not state that the four pack of detectors included " quick connect AC wire harnesses." When I placed my order I separately ordered these harnesses and spent an extra $12 I did not need to spend. Disappointed that Kidde did not just make these units with the original connectors in the first place. It's not really that difficult to disconnect the old connector and rewire the circuit with the new connector unless you are 69 years old with an arthritic neck wobbling on a step ladder. Now I have 4 extra connectors that I will never need.

The good: simple brilliance of the battery access on the ‘front’The bad: these died after 4 years of use. They’re supposed to last 7-10 years/technically they lasted 7 years From when they were built, but I didn’t realize they were ALREADY 3 years old by the time I purchased them.Net: I now know why they were cheaper on amazon, because they were already 3 years closer to expiring than if I bought ‘fresh’ ones

These Firex smoke detectors installed fairly easily, even though my ancient original wired-in Kidde-brand detectors use a different base plate and wiring plug. The new base plate installs on standard electric outlet box screws, and the included pigtail plug can replace the old pigtail plug using the wire nuts that are probably already in the ceiling. I also bought conversion adapters between the old and new plug configurations, and that sped up replacement on some detectors, but probably wasn't worth the cost.For new construction, you could use a common wire to connect all your smoke detectors, so that they all go off if one detects smoke. An interesting feature, but I don't really need it. I tested the installed detector with some smoke, and it went off went it should have. I'm hoping that it won't go off as quickly as the last model, which activated every time we fried something on the stove.A good value, especially considering that it also includes a 9-volt backup battery. Hopefully, these detectors last as long as the old ones (20 years), even though I'm now learning that the ionization isotope used decays and is no longer sensitive after only 10 years!

These have replaced old Firex Models 120-1072B.( Hard wired). The old units were going off in the Hottest part of the day, But usually only 2 -3 units. The House temp was set at 75. But they go off the same time every day. When they started going off at night I Though they were probably used up and time for replacements. So decided on these since it was a 4 pack and We'll need 7. And I seen other reviews that people used for the same old model.The ones I received were dated Feb 2021 (now July 21) They came with a battery, and hard wire to connect the new smoke detector to the house wiring. Not that much of a problem once you find which breaker it is to turn the power off. Just 3 wire connections and new wires matched my old wire colors. Installed, pulled battery tabs and powered up(120v). Blinked red twice, then went green. Green is on to show you have 120 volts. Push the test button and all alarms went off.I like the fact it does not have to be removed to refresh the battery. Battery door is accessible when installed. It also has a Low Battery "Chirp". You can push the test/ Hush button and it will silence the chirp for13 hours. It has a list of batteries you can use in the unit, however they say NOT to use Lithium Batteries.Will see how these work and if okay, will order more to replace the rest of my old units.

This smoke detector is nearly the same as the 10 year-old unit it replaced - FADC 4618. The back up power plug is different. I purchased the adapters which made replacement a snap. It took all of five to ten minutes to replace the old unit with the new. One of the electrical boxes was too shallow to accommodate the old plug and the adapter with it. The old plug had a tab that sat flush with the detector. It was easy to snap it off, then it fit. One thing I liked is that the bezel is slightly larger than the older one. It has multiple slots and screw holes to fit just about anything, and it covered the old drywall patches around the edge where the old bezel was.I should be good for another ten years now.

Replacement looks almost exactly the same as originals, 13 years ago. Mounting plate slightly larger, which doesn't matter (and might hide any marks on the ceiling). Biggest complaint is that the wiring harness isn't the same, so you either have to pull the wires out of the ceiling box and rewire all, or buy the Kidde KA-F Quick Convert Adapter. I went with the adapter, so that I didn't have to mess with rewiring.