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Internet # 100045210

Model # 21029915

Store SKU # 201001

Store SO SKU #1000497008

Firex Plug-in Carbon Monoxide Detector, 9-Volt Battery Backup and Digital Display, CO Detector

$42.97
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  • Carbon monoxide alarm plugs directly into wall outlet
  • 9V battery backup for protection even during power outages
  • Digital display updates CO level in PPM every 15 seconds
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Product Details

About This Product

The digital readout of the Kidde Plug-In Digital Carbon Monoxide Alarm with 9-Volt Backup continuously displays carbon monoxide levels from 30 to 999 parts per million (PPM) and will sound an 85dB alarm when dangerous levels are reached. The carbon monoxide level sensed is continuously displayed and updated every 15-seconds and the peak level memory shows the highest level of carbon monoxide present since the last time the unit was reset or unplugged. Protection continues during power outages thanks to a 9-Volt battery backup.

Highlights

Product Information

Internet # 100045210

Model # 21029915

Store SKU # 201001

Store SO SKU #1000497008

Specifications

Dimensions: H 6 in, W 3.5 in, D 1.9 in

Dimensions

Product Depth (in.)

1.9 in

Product Height (in.)

6 in

Product Width (in.)

3.5 in

Details

Alarm/Detector Features

Battery Back-Up, Digital display, Hush Button

Alert Type

Siren

Battery Type Required

9-volt

Commercial/Residential

Home

Connector/Contact Type

None

Fixed or portable

Fixed

Included

Batteries

Pack Size

1

Power Source

Plug-In

Returnable

90-Day

Voltage (V)

120

Warranty / Certifications

Certifications and Listings

UL Listed

Questions & Answers

79Questions
caret
Q:How many years will this work?
by|Apr 13, 2024
1 Answer
Answer This Question

A:  Hello. The unit is good for 10 years from first use.

by|Apr 15, 2024
    caret
    Q:My alarm went off an hour ago and then now. Still showing zero. Does that mean battery has to be replaced. Unit is 4 years old
    by|Jan 1, 2024
    1 Answer
    Answer This Question

    A:  Hello. Was it one chirp every 30 seconds to a minute or was it 4 quick beeps, a pause, 4 quick beeps, a pause, over and over again? If it was one chirp every 30 seconds to a minute and it was saying "Lb" on the display then that is a low battery. If the unit is giving 4 beeps, a pause, 4 beeps, a pause, over and over again with a number then that is an alert for carbon monoxide. Call us with that alarm in hand at 1-800-880-6788 so we can tell you more about what the alarm is doing.

    by|Mar 15, 2024
      1 found this answer helpful
      caret
      Q:Is this good for propane detection
      by|Nov 30, 2023
      2 Answers
      Answer This Question

      A:  No, you need an explosive gas detector for that. You should have a carbon monoxide detector nearby if there is combustion happening inside though (ex: furnace).

      by|Dec 19, 2023

        A:  Hello. No, this unit only detects carbon monoxide.

        by|Dec 27, 2023
          caret
          Q:Does this product come with the 9-volt battery or do I need to buy separately?
          by|Oct 9, 2023
          1 Answer
          Answer This Question

          A:  Hello. Yes and yes. The unit comes with a courtesy initial 9 volt battery which should last 6 months to a year. A new battery will need to be purchased every 6 months to a year of the type, brand, and model listed in the owner's manual.

          by|Oct 25, 2023
            Showing 1-4 of 79

            Customer Reviews

            4.7 out of 5

            • 4.7 out of 855 reviews
            • 96% recommend this product
            Filter by:
            Showing 1-10 of 855 reviews
            We have had a carbon monoxide detector that does not have a digital display and we have had it go off several times. Since there is no readout we error on the side of caution and have the Fire Department come out on a non-emergency run and bring their sniffers and check the house to insure that we are safe only to find that the batteries we used were depleted. A long time ago we had a digital detector in our house and it went off and showed numbers. A call to our neighbor that was a captain on the Fire Department told us to leave the house and call the Fire Department. Upon arrival they found the carbon monoxide levels extremely high and upon further investigation it was found that our heat exchanger in our furnace had malfunctioned. If we had ignored this alarm I would not be setting here to right this review. We have gone back to all digital display detectors in our new house. Like I said the non readout one caused us grief and has been properly disposed of and replaced with these digital readout ones. I feel more confident with these alarms in our house and sleep sounder knowing that of the 4 alarms that we have we are fully protected. I highly recommend these detectors. We give them to people that are moving into their first home as a house warming gift.
            by
            • Verified Purchase
            Rating provided by a verified purchaser...
            Rating provided by a verified purchaser
            by
            • Verified Purchase
            I bought the CO detector to replace one of a similar model that shut itself down when the sensor ...
            I bought the CO detector to replace one of a similar model that shut itself down when the sensor reached the end of its life. I have no problem with the product's performance, but I am annoyed that it was necessary to replace an entire instrument because one component predictably failed. This is hardly a new problem for the electronics industry. a century ago radio manufacturers faced a similar problem with vacuum tubes that had finite lives. The radio companies, however, were considerably smarter than Kidde. Rather than force their customers to trash the entire receiver due when a tube burned out, they had the tubes plug into sockets so the owner could replace then while preserving the remainder of the set. Why can't Kidde do likewise. Heck, they could even use existing tube bases and sockets. The attache photo shows an example.
            by
            • Verified Purchase
            • Recommended
            2 found this review helpful
            My unit just reached it's "End of Life". It only took 9 years! Mine was manufactured in October 3...
            My unit just reached it's "End of Life". It only took 9 years! Mine was manufactured in October 31st, 2011. I will be buying another one and hopefully get the same duration or something similar with the new one which is now called "Nighthawk"
            by
              • Recommended
              3 found this review helpful
              The product was relatively easy to assemble. The only problem I had was the battery Compartment w...
              The product was relatively easy to assemble. The only problem I had was the battery Compartment was a little to open. Once that was open, I had no problem.
              by
              Response from Kidde ExpertNov 12, 2019
              Hello JJ,
              Thank you for your input. This information will be relayed to product development.
              • Verified Purchase
              • Recommended
              1 found this review helpful
              Love this monitor, it cycles ever so often and displays the reading. Also, plugs into an outlet s...
              Love this monitor, it cycles ever so often and displays the reading. Also, plugs into an outlet so no batteries to go dead. Purchased a couple of weeks ago.
              by
              • Verified Purchase
              1 found this review helpful
              I read that there is an internal clock that limits the unit to seven years of service and just pu...
              I read that there is an internal clock that limits the unit to seven years of service and just pulled mine because I'm getting a chirp and low battery indication. It was manufactured 8/13/98 and had been displaying 0 ppm CO and flashing the decimal point to indicate operation. If the expiration clock feature is true, it must have been added after I purchased mine. The model number is 900-0076-00 and there are no expiration instructions on the unit. Other than battery replacement, the unit requires no special attention and hasn't even collected dust. Speaking of battery replacement, that is a weak point. Applying pressure to the access panel and sliding in the direction of the arrows may not work as well as prying it loose with a screwdriver. There is a remote, wired mounting option but I chose to plug the unit directly into an outlet. Very easy installation - plug and play. My old unit looks exactly like the one pictured but with a bit of yellowing on the front face at the power transformer location. I guess it's time for a replacement and unfortunately, electronics go to the landfill.
              by
                • Recommended
                1 found this review helpful
                This is extremely well engineered!!! You can remove the transformer to mount away from a plug, o...
                This is extremely well engineered!!! You can remove the transformer to mount away from a plug, or simply plug it into an outlet. It has a small tap at the bottom you can pull out when plugging directly into the wall outlet to compensate for the wall outlet projecting out from the wall to keep it flat. It comes with a battery, so is dual power.
                by
                • Verified Purchase
                • Recommended
                6 found this review helpful
                Easy to understand instructions. Easy to get working. The hardest part was getting the unit out o...
                Easy to understand instructions. Easy to get working. The hardest part was getting the unit out of the plastic packaging.
                by
                • Verified Purchase
                • Recommended
                1 found this review helpful
                When my 7 year old CO detectors started timing out, I bought this 6-pack to replace them (and to ...
                When my 7 year old CO detectors started timing out, I bought this 6-pack to replace them (and to add a couple more for the second bedroom, and garage). I especially like this model that plugs in but has a battery backup, and displays the most recent %CO reading. The power block can also be extended from the body, or plugged in direct.
                by
                • DIY
                • Verified Purchase
                • Recommended
                3 found this review helpful
                Showing 1-10 of 855 reviews

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