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Home / Products / Carbon Monoxide Alarms

Universal Security Instruments Plug-In 2-in-1 Carbon Monoxide and Natural Gas Smart Alarm with Battery Backup (MCND401B)

  • Universal Security Instruments Plug-In 2-in-1 Carbon Monoxide and Natural Gas Smart Alarm with Battery Backup (MCND401B)
  • MCND401B
  • MCND401B
  • MCND401B
Plug-In Alarm | Display Screen
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Regular: $64.95
Price: $47.95
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Bundle Price: $273.30

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5 - 28 Customer Reviews
  • Features
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  • 2-in-1 Carbon Monoxide and Natural Gas Alarm
  • 120-Volt AC Plug-In Alarm with Battery Back-Up
  • Back-up Battery Continues protection in the event of a power outage
  • 9-Volt Energizer Alkaline Battery Included
  • Digital Display Screen with Three LED Colors Indicating Power, CO and Natural Gas
  • Quick Activation Pull Tab
  • Microprocessor Software Virtually Eliminates Nuisance Alarms
  • Compact Plug-in Design
  • No Additional Mounting Required
  • Swift Installation Process
  • 5 Year Limited Warranty
  • Meets New Laws & Legislations - This alarm exceeds industry standards, and is listed to UL Standard UL 217 and is California State Fire Marshal approved.
The Universal Security Instruments Electric MCND401 Plug-In Carbon Monoxide and Natural Gas Smart Alarm is a 2-in-1 device that provides double the protection with a single installation. This dual-sensing alarm protects against two deadly household threats: carbon monoxide and natural gas (or methane). Perfect for new or replacement installations, the 120-volt AC alarm is suitable for houses, apartments and mobile homes. The compact plug-in design covers only (1) outlet for a fast and easy installation with no wiring required. This alarm features microprocessor intelligence to eliminate nuisance alarms, a single silence/test button to quiet a non-hazardous alarm and an end-of-service life warning that sounds when it's time to replace the battery (approximately 7 years from activation). The digital display screen provides carbon monoxide PPM (parts per million) levels and displays 'GAS' during an occurrence. Peak CO levels are recorded with the memory button and (3) LED colors display the status of the alarm, power, CO and gas in your home. The 9-volt alkaline battery (included) continues protection in the event of a power outage.

This alarm is ETL Listed to UL Standard 2034 & UL1484, California State Fire Marshal approved and Federal Housing Authority (FHA) approved to exceed industry standards. For maximum protection, install an alarm inside every bedroom, outside every sleeping area and on all levels of the dwelling. The Universal Security Instruments Electric MCND401 Plug-In Carbon Monoxide and Natural Gas Smart Alarm comes with a 5 year limited warranty.


Recommended replacement for the following obsolete models:
- CD-9690

Product Details
  • Warranty: 5 year Limited Warranty
  • Alarms Power Source: 120 volt (plug In & battery backup)
  • Alarm Sensor Type: Metal Oxide
  • Manufacturing Credits: ISO 9001 certified factory, UL listed & CSFM listed
  • Packaging: Easy Open Box Packaging
  • Product Dimensions (W x H x D): 5.0 x 5.0 x 2.25 in.
  • Product Weight: 0.57 lbs.
Product Specs
UPC:
042741204019
MPN:
MCND401B
Category:
Carbon Monoxide Alarms
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: 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.

  • MCND401B USI Alarm Manual
  • MCND401B Alarm Spec Sheet
  • MCND401B CSFM Listing
USI Digital Display Plug-In 2-in-1 CO and Natural Gas Smart Alarm (MCND401B) Video
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Customer Reviews

5

Average score based on 28 reviews

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5
Write A Customer Review Review
USI Digital Display Plug-In 2-in-1 CO and Natural Gas Smart Alarm (MCND401B) Reviews

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5 - Reviewed: 03/10/2023 by Timothy U

Dual gas alarm

As advertised. Arrived quickly. Hopefully it works if there is ever co2 or natural gas in house

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5 - Reviewed: 10/24/2022 by Kathy S

So far it works well!! No problems at all!!

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5 - Reviewed: 07/16/2022 by Barry S

CO and Natural Gas Detector

Items performed as advertised

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5 - Reviewed: 02/14/2022 by Derek N

Great peace of mind

Installed near our living room where the gas fireplace is. You just never know when things could happen, it's good to know that this unit is there to alert us.

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5 - Reviewed: 12/29/2021 by Elizabeth B

Simplicity is the word!

It couldn't be easier to be protected from the deadly airborne killers, carbon monoxide and natural gas. Simply plug it into a wall socket, set an expiration date on your iPhone and your good to go. Just forget about it!

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5 - Reviewed: 11/21/2021 by Ronald G

Great Product

I find the product to be exactly what i needed in the house. I have a generator & this product fits perfectly. Fast delivery & easy to install. Certainly creates peace of mind in the entire house, knowing it is working to keep the family saye. Thank You.

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5 - Reviewed: 11/19/2021 by William B

Universal Security Instruments Plug-In 2-in-1 Carbon Monoxide and Natural Gas Smart Alarm

It is hard to test a Carbon Monoxide and Natural Gas monitor, but the Unit quality appears to be high and the packaging was very minimal.

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5 - Reviewed: 11/04/2021 by Ronald G

Great Product

Received the product quickly. Very easy to install & provides the security I need within the house. Really like the 2 in 1 feature with the battery backup, adds the safety & peace of mind for the family. Thanks.

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5 - Reviewed: 10/18/2021 by Jennifer W

CO and CH4

Hasn't been needed yet but install went well.

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5 - Reviewed: 10/11/2021 by Raghava C

Nice product

It was easy to set up and it is working fine.

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5 - Reviewed: 10/08/2021 by Bill M

owner

I have used these for years, and replaced existing units that expired.Plus the multi detection feature is additional protection

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5 - Reviewed: 09/08/2021 by Evanthia C

great product

works as indicated and very easy to use and understand.

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5 - Reviewed: 05/10/2020 by Steven Roberts

Nice unit

Item was well packed and seems good quality.

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5 - Reviewed: 05/06/2020 by David Marco

Product worked well...delivery was quick, installation went well. Easy online ordering.

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5 - Reviewed: 02/06/2020 by Deborah Laurain

Carbon monoxide alarm

This product is excellent. I have had this in my home for many years and I trust it will keep my family safe. I like that it detects 2 dangerous factors gas and carbon monoxide!

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5 - Reviewed: 01/16/2020 by David Langston

Works well as per documentation, no false alarms

It works correctly. There have been no false alarms, but apparently I have no CO or CH4 in my furnace/laundry room either, so I can't evaluate those functions. Tested the alarm test at a peak level of 116 dBA with a sound meter. That should wake me up if it ever really alarms.

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5 - Reviewed: 11/28/2019 by Robert Gilliam

Easy Installation

Since most outlets are 2 or less from the floor, I installed a duplex outlet about 12 above a light switch on the wall. Easy using an old work junction box. This solved the correct height debate by placing it halfway up the wall. Plugged in the detector and Voila!

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5 - Reviewed: 09/17/2019 by Ronald Carver

CO and Nat Gas Wall Device

Excellent product at a great price.

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5 - Reviewed: 04/10/2019 by Jeffrey Muehring

For the price, It's better than any detector sold in a retail store.

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5 - Reviewed: 09/08/2018 by Thomas Petray

Carbon Monoxide/Natural Gas Alarm Working well

Kept getting some various alarm sounds and different numeral codes, but it stopped after the third reset and appears to be working quite well now.

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5 - Reviewed: 04/06/2018 by Leon Harvin

Alarm

Alarm instruction was easy to understand. Plugged into electric receptacle and it functioned perfectly.

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5 - Reviewed: 03/26/2018 by Justin Frederick

Great alarm

The alarm is quick and easy to install and with a sealed backup battery no worries about changing.

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5 - Reviewed: 02/18/2018 by Brian Tucker

One Wall Plug

The convenience of being able to protect and alert the home owner from just a wall plug is priceless. No wiring to hook up, just plug it in and be protected.

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5 - Reviewed: 02/15/2018 by Yante Gonzalez

YG

excellent product

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5 - Reviewed: 02/12/2018 by Yante Gonzalez

YG

Excellent Product. Easy to install and work perfect.

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5 - Reviewed: 08/31/2017 by PEG HUBER

Both tested well so far. Put my mind at ease. Peg H.

Rating: 4/5Rating: 4/5Rating: 4/5Rating: 4/5Rating: 4/5 - Reviewed: 10/27/2016 by John Licata

Good

I like product

Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5Rating: 5/5 - Reviewed: 06/30/2016 by William Knoblauch

Easy unit to install

All I had to do was plug it in, it was good to go. Easy to read and understand.

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