Universal Security Instruments Hardwired Ionization Smoke and Fire Alarm with Battery Backup, Model MI106

Just as described . Great easy to install replacement

As our smoke alarms time out (they should be replaced at least every ten years) we have been buying the same brand and this model so that we don't have any compatibility issues. Our house has a lot of smoke and CO detectors, and I'm thankful to the builder for that, and if one goes off it triggers the rest to sound as well. The new USI ones have a 'locate' function that will tell you which detector initiated the alarm if you have one that is too sensitive or otherwise giving false alarms. We don't have that issue, but I will appreciate it if we ever do.

I tried to return this item recently, but Amazon says that it is too late to return. I tried plugging the alarm into the hard wire and it sparked and shorted out. Yes, the hard wiring was done correctly. It does not and did not work.

Bought this to replace a USI with battery that decided to shriek even after cleaning. Same plug in so no rewire needed.

Good Candidates • Large homes • Multiple floors • Prewired alarm consoles Bad Candidates • Every other type of structure GENERAL For smaller homes or those not hard wired to alarm console (e.g. Honeywell, Ademco) there are far easier solutions with self-contained units that are powered for life with a lithium battery. If you only need only one, maybe an expensive Nest model with a webcam would be good ($100-$200). Units are becoming available that will connect wirelessly (i.e. Z-wave, zigby, 802.11 Wifi) that may afford more flexibility in placement. Although, if you have an existing home with 6+ detectors then wired-in units are the way to go. This is significantly less expensive and will still allow you to connect through modern monitoring platforms if you buy a digital gateway (so you can be alerted by text, email, or web monitoring) like Honeywell's vista control module. THE GOOD • Economical • Reasonably easy to install • Alerted at EVERY location if there is smoke at ANY location • USI has made a better alarm than 10 years ago with the battery door, appearance and test button THE BAD • To move from the older USI models (e.g. 1204) to these is to completely start over. If you ever wanted to consider another brand (e.g. First Alert, Kidde) now is the time because there is no advantage to staying with USI. The new models are NOT compatible with any of the older models (see attached picture from the manual). Ever skeptical, I tested this by replacing 7 detectors and leaving 1 of the Model 1204 and then pushing the test button. All the new models "chirped" on the relay, but the old one did not. • The wiring harness has totally changed, so that is not reusable. (see picture) • The ceiling mount has changed so that needs to be traded out too. (see picture) THE (UGLY) PROCESS • There is some overhead in getting started because you need to shut off the circuit breaker before you get started. • The only other tool I needed was a Philips screwdriver. • You may consider ear protection as some of the old detectors will chirp as they removed. • It took me about 15 minutes to change out each detector once I got going. • In my house the Yellow alarm wire needed to be wired in with the Red house wire. (see picture)

My 12 year old smoke/fire alarm outlived its life and started beeping (loudly) at random times of the day, for undetermined lengths of time. Family and guests were understandably annoyed. I changed the battery but the beeping continued...until I bought this as a replacement. No more beeping, no more false alarms, no more disturbed sleep.

Easy installation! Product is exactly as advertised.

This was an exact replacement for our ceiling mounted smoke alarm. Easy install.