USI Electric Hardwired 2-in-1 Universal Smoke Sensing Smoke and Fire Alarm with Battery Backup (MDS107)

  • USI Electric Hardwired 2-in-1 Universal Smoke Sensing Smoke and Fire Alarm with Battery Backup (MDS107)
  • USI Electric Hardwired 2-in-1 Universal Smoke Sensing Smoke and Fire Alarm with Battery Backup (MDS107)
  • USI Electric Hardwired 2-in-1 Universal Smoke Sensing Smoke and Fire Alarm with Battery Backup (MDS107)
  • USI Electric Hardwired 2-in-1 Universal Smoke Sensing Smoke and Fire Alarm with Battery Backup (MDS107)
2-in-1 | Smart Alarm
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  • Universal Smoke Sensing Smoke and Fire Alarm
  • Responds 87% Faster to Slow Smoldering Fires
  • Responds Quickest to Fast Flaming Fires
  • 120 Volt AC Wired-In + 9 volt Alkaline Battery Operated
  • Loud 85 db Alarm
  • Microprocessor Eliminates Nuisance Alarms
  • New Universal Smoke Sensing Technology
  • Power and Alarm LED's
  • Test/Silence Button
  • Product End-of-Service Life Warning
  • 2 Tamper Resistant Locking Features
  • Battery Activation Tab
  • Quick Draw Battery Drawer
  • Interconnectable with up to 24 Compatible Devices
  • Ideal for Homes, Apartments and Mobile Homes
  • Listed to UL217 Standard
  • California State Fire Marshal Approved
  • 10 Year Limited Warranty
The USI Electric MDS107 Smoke and Fire Alarm responds quickly to both fast-flaming and slow-smoldering fires to protect your family against deadly threats in the home. Perfect for new or replacement installations, the 120V AC hardwired alarm is suitable for houses, apartments and mobile homes. Universal Smoke Sensing Technology responds 87-percent faster to slow smoldering fires and responds quickest to fast-flaming fires. The alarm is fully interconnectable with all USI and Universal 120V alarms using existing wiring and mounting. Auto sensitivity calibration provides superior nuisance alarm protection and creates consistency in alarm sensitivity.

This alarm has additional automatic features including a self-diagnostics check to ensure proper operation, a sensitivity adjustment for changes in temperature or humidity and an end-of-service life warning that sounds when it's time to replace the battery. The 9-volt alkaline battery (included) continues protection in the event of a power outage. This alarm features a front-loading battery drawer for replacing the battery without removing the alarm from the bracket. Mount the bracket to any standard wiring junction box and use the large mounting base to cover imperfections in drywall. For maximum protection, install an alarm inside every bedroom, outside every sleeping area and on all levels of the dwelling. The USI Electric MDS107 Hardwired Universal Smoke Sensing Smoke and Fire Alarm comes with a 10 year limited warranty.
  • Warranty: 10 year Limited Warranty
  • Alarms Power Source: 120 volt hardwired with battery backup (Battery Included)
  • Alarm Sensor Type: Universal Smoke Sensing Technology (Ionization & Photoelectric)
  • Manufacturing Credits: ISO 9001 certified factory, UL listed & CSFM listed
  • Product Dimensions (W x H x D): 5.75 x 6.70 x 1.75 in.
  • Product Weight: 0.67 lbs.
Product Specs
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Average score based on 20 reviews

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5

Reviewed: 06/19/2019 by Dale Steadman

works great

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Very Accurate Description

Reviewed: 02/22/2019 by Tom De Martini

This alarm really works. It does respond well to even a small amount of smoke. I accidentally burned some food on the stove top and the alarm about 20 feet away started blaring. The only thing to realize is the potential for the smoke to get trapped inside an interior compartment of the alarm itself. The alarm will keep blaring if you reinstall it. When this happens there is no way to blow out the trapped air and the alarm must be replaced by a new one. This, however, could be true for any smoke alarm. Overall this alarm does work very well.

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Replacement

Reviewed: 01/01/2019 by Pietro Dova

Nice to see that the pin connection remains unchanged from 2011. But for some reason the clamping system has changed from prior model so the ceiling mount needs to be replaced with the new one provided to re-attach the unit to the ceiling.

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Easy install

Reviewed: 12/22/2018 by Jake Repash

Easy install and so far have worked good without any false alarms.

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Replacement Alarms

Reviewed: 12/08/2018 by Wayne Jertson

I'm very pleased with my new Smoke/Fire alarms. Easy to install and test. Good product!

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Replaced 6 Smoke and Fire Alarms

Reviewed: 11/02/2018 by Bruce E. Stuck

I discovered the USI Model 1204 Smoke and Fire Alarm Detectors in my home were 5 years beyond their 10 year lifetime! From information on the detector, I contacted USI, Inc. and was promptly sent an email that contained a video link on replacing the detectors. The link answered all my questions. Hence, I immediately ordered 6 Ea. MDS107 Smoke and Fire Detectors that arrived about 5 days later. I replaced and tested all 6 and they worked perfectly in our alarm system. The efficient assistance provided by Michele Metcalfe at USI, Inc., Owings Mill, Md was superb. Thanks for excellent customer service.

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5

Reviewed: 10/10/2018 by Eugene Smith

First time ordering but was very happy with the quality service.

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Happy Customer

Reviewed: 10/01/2018 by A.R.

I recently purchased this item directly from USI. Product arrived as expected and in the condition described on their website. Excellent Value..... Thanks

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Pretty Much Plug and Play

Reviewed: 09/28/2018 by Greg Griffith

Very pleased with warranty support from my old house. I changed out all outdated models in my new home. Simple swap out from one manufacturer to another. 2 mounting screws and a pigtail. Also comes with battery so it's good to go.

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5New Smoke Alarms

Reviewed: 09/19/2018 by Kevin Kaari

I recently bought 10 new hardwired detectors to replace my existing USI detectors that aged out. The new ones installed quick and easy. No issues with any of them. I am happy with my purchase.

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Replace old units

Reviewed: 09/15/2018 by Chester Hewitt

Installation of new smoke and fire detectors was simple and easy, mounted to existing boxes with ease and rewireing was also simple.

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5

Reviewed: 09/10/2018 by Joseph Armstrong

Well satisfied with my purchase! Four units boxed together for shipping. New 9-volt battery included in each unit. Relatively easy to replace / install. MDS107 is well designed and engineered. Battery drawer is a wonderful design change over my original USI detector. Original detectors manufactured in 1999 or 2000. If offered, I would rate my MDS107s as a 6 - Outstanding.

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Mds107 review

Reviewed: 05/07/2018 by ruth betcher

The alarms installed wonderfully easy. They are great.

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Best Ceiling Option

Reviewed: 05/02/2018 by Kristin Pardue

Best option as CO should be monitored down low, not on ceiling. Easy installation.

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Replacing old hardwired alarms

Reviewed: 03/23/2018 by Charles Dove

Replaced whole home hardwired ion alarms that were over 10 years old for my parents. Have these alarms in my home for a few months now and am well pleased. Learned from research that photoelectric alarms provide needed coverage in addition to ion technology alarms. These are among the best priced alarms that have both types of sensors.

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A: The smoke alarm chirps to indicate a "low battery" condition, meaning the battery needs to be replaced. Battery powered smoke alarms will chirp a minimum of 30 days before the battery completely loses power.

AC powered smoke alarms with battery backup will chirp indefinitely assuming AC power is present; if battery power is low, or battery is removed; until a fresh battery is installed. Approved replacement batteries are listed on the back of each smoke alarm and in the user's manual.

Certain model smoke alarms with a silence button (designed to silence the alarm during a nuisance alarm) may chirp to indicate the smoke alarm is in the silence mode. The chirp will stop after approximately 8 minutes and the smoke alarm will return to its normal operation.

A: The flashing red light gives a visual indication that the smoke detector is functioning properly. It also indicates a working battery is connected to the smoke alarm.

A: When a green light is present on your smoke detector, it means that AC power is currently operating the alarm.

A: If the green light on your smoke detector is not on, it means the AC power has been interrupted to the alarm. Check the circuit breaker and AC wiring to make sure power is still reaching the smoke alarm.

A: When interconnected alarms are alarming, the smoke alarm which initiated the alarm, either by test button or sensing smoke, will flash the red LED light approximately once per second. The red LED light on the other non-initiated interconnected smoke detectors will not be lit but will sound the alarm.

A: The NFPA 72 standard states the interconnect limit is 12 smoke alarms and up to 6 other alarms (heat alarms or carbon monoxide detectors) for a total of 18 total alarms. With 18 alarms interconnected, up to an additional 6 relay modules may be interconnected (for a maximum of 24 devices).

If battery backup alarms and non-battery backup alarms and accessories are mixed in an interconnect system, all devices without battery backup WILL NOT operate during an AC power failure.

CAUTION: USI alarms and accessories should only be interconnected with other USI alarms and accessories. Connecting devices from another manufacturer to USI devices may result in nuisance alarms, failure to alarm, or damage to one or all of the devices in the interconnect system. All interconnected USI alarms should be powered by the same fuse or circuit breaker. Smoke alarms shall not receive their power from a circuit that is protected by a ground fault circuit interrupter. Improper connection will result in damage to the alarm, failure to operate, or a shock hazard.

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