The USI Electric MDSCN111 Hardwired Smart Alarm is a 4-in-1 device that provides quadruple the protection with a single installation. This 120-volt AC alarm protects against (4) deadly household threats: fast-flaming fires, smoldering smoke, carbon monoxide and natural gas (or methane). Perfect for new or replacement installations, the MDSCN111 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. 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 MDSCN111 Hardwired Universal Smoke Sensing Smart Alarm comes with a 7 year limited warranty.
Warranty: 7 year Limited Warranty
Alarm Power Source: 120 volt hardwired & 9 volt battery backup
Combination Alarm - 05/30/2018
Reviewer: Charles Dove
Extremely good value for this many functions. Works with many other USI alarms. Wanted one alarm with CO detection in room with ventless propane fireplace that would communicate with other non CO alarms in the rest of the house that I was replacing. Easy to install, simply wirenut the leads on harness to your boxes wires and all set
Best alarm - 03/26/2018
Reviewer: Justin Frederick
This a great to have co and natural gas with a dual sensing alarm. Great peace of mind. Easy to install.
YG - 02/12/2018
Reviewer: Yante Gonzalez
Excellent Product. Easy to install and work perfect.
Reviewer: Neidra Akers
This alarm is the best. I would suggest for anyone to purchase it. We now have 3 within our house.
Reviewer: John Maccio
Pleasure to do business item in stock received right on time and the person I spoke with was very helpful will do business again
Reviewer: John Scarlata
The alarm was easy to install and is effective for multiple sources of fire, smoke etc
Reviewer: Rick Rose
So far so good
Upgraded - 01/02/2017
Reviewer: John Lemire
I was in need of replacement smoke detectors. I decided to upgrade on detector on each level with the 4-1 detector. Thisent will eventually replace my CO2 detector that I have had for some years. Easy to install using the old wall plates and wire harness.
Reviewer: Dexter Hernandez
Easy to install. Relief to know my family is protected.
USI 4-in-1 Hardwired Alarm - 09/23/2016
Reviewer: Thomas Concolino
Nice product! Was delivered on time and had no damages.
Reviewer: Richard Kilmer
Easy to install - 12/13/2014
Reviewer: Brian Peters
Easy to install and gives me piece of mind.
Im a Firefighter - 11/02/2014
Reviewer: Tony Smith
I love it easy to put up and you can hear it in the bed rooms. And I love that it protects against all 4 .
Q: WHY DOES MY SMOKE ALARM 'CHIRP' APPROXIMATELY ONCE EVERY MINUTE?
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.
Q: WHAT LEVELS (PPM) OF CARBON MONOXIDE CAUSE AN ALARM?
A: Carbon monoxide alarms are designed to alarm before the average healthy adult feels symptoms. Since you cannot see or smell CO, never assume it's not present. Underwriters Laboratories Inc. Standard UL2034 requires residential CO alarms to sound when exposure times and exposure levels of CO in the chart below. CO alarm levels are measured in parts per million (ppm) of CO over time (in minutes). The UL2034 Required Alarm Points are:
If the Alarm is exposed to 400 ppm of CO, it must alarm between 4 and 15 minutes.
If the Alarm is exposed to 150 ppm of CO, it must alarm between 10 and 50 minutes.
If the Alarm is exposed to 70 ppm of CO, it must alarm between 60 and 240 minutes.
Q: WHAT DOES IT MEAN WHEN THE RED LIGHT ON THE ALARM FLASHES APPROXIMATELY ONCE EVERY MINUTE?
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.
Q: IS CARBON MONOXIDE HEAVIER THAN AIR?
A: Carbon monoxide is not heavier than air. A carbon monoxide alarm should be installed in a location where the alarm will stay clean, and out of the way of children or pets. Refer to the user's manual for specific installation requirements.
Q: WHERE SHOULD I INSTALL MY CARBON MONOXIDE ALARMS?
A: It is very important to install a carbon monoxide alarm outside each separate sleeping area, and for maximum protection, install one in every bedroom. Many states now require installation of a carbon monoxide alarm inside each bedroom. For added protection, placement of an additional carbon monoxide alarm at least 15-20 feet away from the furnace or fuel burning heat sources is recommended. Install carbon monoxide alarms a minimum of 10 feet from sources of humidity like bathrooms and showers. In multiple-story dwellings, install one carbon monoxide alarm on every level. If you have a basement, install a carbon monoxide alarm at the top of the basement stairs, and in each separate sleeping area.
Q: WHAT AREAS SHOULD I AVOID INSTALLATION OF A CARBON MONOXIDE ALARM?
A: Do not install carbon monoxide alarms in garages, kitchens, furnace rooms, or in any extremely dusty, dirty, humid, or greasy areas. Do not install alarms in direct sunlight, or areas subjected to temperature extremes. These areas include unconditioned crawl spaces, unfinished attics, un-insulated or poorly insulated ceilings, and porches. Carbon monoxide alarms should not be installed in outlets covered by curtains, heavy furniture or other obstructions. Do not install in turbulent air-near ceiling fans, heat vents, air conditioners, fresh air returns, or open windows. Blowing air may prevent carbon monoxide from reaching the CO sensors.
Q: WHAT DOES THE CONTINUOUS GREEN LIGHT ON MY SMOKE ALARM INDICATE?
A: When a green light is present on your smoke detector, it means that AC power is currently operating the alarm.
Q: THE GREEN LIGHT ON MY SMOKE ALARM HAS GONE OUT, WHAT DOES THIS MEAN?
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.
Q: HOW CAN I TELL WHICH SMOKE ALARM IN A MULTI-STATION SYSTEM INITIATED THE 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.
Q: HOW MANY SMOKE ALARMS OR DEVICES CAN BE INTERCONNECT AT ONE TIME?
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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