FIRST 2021 ALERT Hardwired Wireless Smoke Alarm with discount Photoelectric Sensor and Battery Backup, SA521CN-3ST sale

FIRST 2021 ALERT Hardwired Wireless Smoke Alarm with discount Photoelectric Sensor and Battery Backup, SA521CN-3ST sale

FIRST 2021 ALERT Hardwired Wireless Smoke Alarm with discount Photoelectric Sensor and Battery Backup, SA521CN-3ST sale
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Brand
FIRST ALERT
Power Source
Battery Powered
Item Dimensions LxWxH
5 x 2 x 5 inches
Item Weight
0.78 Pounds
Sensor Type
Photoelectric

  • Electrical & Heating;Security and Intrusion Monitoring;smoke-detectors

  • Smoke Alarms

    Place at least 10 feet from kitchen/stove, and on the ceiling or high on a wall, no more than 10 inches from top.

    Carbon Monoxide Alarms

    Carbon monoxide alarms can be placed anywhere, not just the ceiling or high on a wall. They should be replaced every 5 to 7 years.

    Fire Extinguishers

    Keep in the kitchen and garage, but make sure to have the right grade for the type of fire that might occur.

    Escape Ladders

    Have at least one if your home has more than one story. Each room needs 2 escape routes; in most bedrooms it's the window, so have a ladder nearby.

    Product information

      Additional Information

    • ASIN: B000EVO9D4
    • Customer Reviews: 4.4 out of 5 stars 624Reviews
    • Best Sellers Rank:
      #25,859 in Tools & Home Improvement (See Top 100 in Tools & Home Improvement)
      #48 in Smoke Detectors & Fire Alarms
    • Date First Available: August 17, 2005
    Manufacturer’s warranty can be requested from customer service. Click here to make a request to customer service.

    Important information

    Bulb Voltage :

    120 volts

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    Product guides and documents

    User Manual (PDF)
    Product Documentation (PDF)
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    What''s in the box

    See more
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    Customer Questions

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    Q: I already have 3 hardwired detectors with no interconnect. I can just replace with these a…

    A: The SA521CN replaces one hard wired unit to provide the wireless connection for add-on wir…

    J. Somers | 7 years ago

    Q: Will this smoke alarm work if you connect it to your wired home smoke alarm system? If one…

    A: The BRK wireless smoke detector also has the hard-wire connections to interface with both …

    ASC2078 | 8 months ago

    Q: Is this device z-wave compatible?

    A: No it is not. Lowes sells some that are z wave compatible. They are called ZSMOKE and ZCO…

    midd | 8 years ago

    Q: Does this come with the plug (to splice) or adapter also? Existing plug has different pin …

    A: In my situation, the unit plugged into the existing hardware system with no problem or mod…

    J. Somers | 7 years ago

    Customer reviews

    4.4 out of 54.4 out of 5
    624 global ratings

    Reviews with images

    Top reviews from the United States

    Kapium
    1.0 out of 5 starsVerified Purchase
    They may ruin your life
    Reviewed in the United States on August 29, 2019
    These are absolutely horrible. They look pretty good and have a nice mounting ring. That is a comprehensive list of positive attributes. My electrician had issues getting them paired and had to spend extra time at it. Of course, that time isn''t free so that''s not a good... See more
    These are absolutely horrible. They look pretty good and have a nice mounting ring. That is a comprehensive list of positive attributes. My electrician had issues getting them paired and had to spend extra time at it. Of course, that time isn''t free so that''s not a good thing. He did succeed and get them all working together and I really wish he hadn''t. Here''s why:

    These things are beyond loud. They are actually painful when they alarm. considering that modern codes have you putting them all over the house this is completely unnecessary. I went with the minimum install which necessitates 7. That means that whenever one of these goes off I have 7 ear-splitting sirens blaring. Now, you may be thinking that might be a good thing, with there being a fire and all. But you''d be wrong because there is no fire.

    So far every single one of them has false alarmed and triggered the whole system. Of course this happens at night, after our toddler is in bed. This isn''t when we''re cooking or taking a steam shower or grinding cement or fogging the dance floor. This is when we''re laying in bed, watching TV, sleeping... and there is absolutely nothing to trigger them. They are new, clean, in a new house, with the windows closed, at 73 degrees and 50% humidity.

    I can honestly say that I absolutely hate these. In fact, I''ve pulled them all down and currently have one other model installed while I look for a new solution. They have ruined our sleep, trained my toddler that fire alarms don''t actually mean there''s a fire and she is absolutely terrified of them and the place on the ceiling where they mount.

    When I get a free moment I''ll contact First Alert to complain and ask for remediation but I strongly doubt they''ll take care of me because I have no interest in replacement units. My recommendation to you is to buy literally any other product.
    15 people found this helpful
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    Digicrat
    4.0 out of 5 starsVerified Purchase
    Easy install; Difficult to program voice; Deafeningly loud
    Reviewed in the United States on March 3, 2019
    Installation was relatively quick and easy -- other than having to install it on a different floor than planned when I unexpectedly discovered that one of my existing alarms was not wired as I thought. (My house should have 4 alarms, it had 3, but apparently only 2 were... See more
    Installation was relatively quick and easy -- other than having to install it on a different floor than planned when I unexpectedly discovered that one of my existing alarms was not wired as I thought. (My house should have 4 alarms, it had 3, but apparently only 2 were interconnected).

    Synchronization with other alarms in the system was quick and easy, particularly since I did so with both alarms in hand prior to installation.

    Programming the ''voice'' alert location, however, is painful. The alarm only has it''s own loud voice which it uses when announcing the locations during programming. I suppose it is a good thing that the alarm is loud in general, but this is strong enough that you are likely to damage your hearing when programming it if you don''t wear ear plugs!

    The programming process is farther complicated by the fact that there is only one button on the device. Programming is done by holding the button down while inserting the battery, and not releasing it until the correct location is heard. Unfortunately, it kept thinking that I let go after it played one or two locations before I finally gave up on correctly programming it.

    Given the cost of these units, couldn''t they make it a bit more user friendly? All they need is to add an extra tiny button dedicated to programming the location on these things (with button presses, not holding while it yells into your face...). And perhaps an extra firmware instruction to reduce the volume when programming and/or testing such that you don''t need hearing protection.

    WARNING: This item is (as are all smoke detectors) considered "hazardous materials" and therefore CAN NOT BE RETURNED. There is no mention of this fact anywhere on the product page or order process. (I did not have to return this item, but needed to return another in the same order due to an unexpected [lack of] wiring issue with one of my existing alarms).
    18 people found this helpful
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    Rex D
    1.0 out of 5 starsVerified Purchase
    Pretty Frustrated!
    Reviewed in the United States on August 21, 2018
    These things seem to work fundamentally, but a real pain to interconnect. The instructions are no help from practical perspective in terms of the process of interconnection. I finally called First Alert and a very helpful customer service rep got me on a different and more... See more
    These things seem to work fundamentally, but a real pain to interconnect. The instructions are no help from practical perspective in terms of the process of interconnection. I finally called First Alert and a very helpful customer service rep got me on a different and more productive path. Once they were all installed, they kept going off at odd times. Then, after 20 seconds or so, they would stop. Tried trouble-shooting the system, but that hasn’t proved helpful either. Now, they are all removed. When I tried to call the phone number on the instructions for professional installation, it doesn’t work. I’m going to try installing them again. If that doesn’t work, I’m not sure what I’m going to do with 14 SA 521’s. They are too small for boat anchors! It’s been quite frustrating to say the least!
    14 people found this helpful
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    bodhicitta_8
    1.0 out of 5 starsVerified Purchase
    WAY.TOO.SENSITIVE.
    Reviewed in the United States on July 17, 2019
    ZERO STARS AND $150 later...If this will be anywhere near your kitchen you better not like to cook on your stovetop or toast bread. Also once it starts with the blaring loud beeping (there is a high pitched beep as well as low pitched one) and the voice and it does not... See more
    ZERO STARS AND $150 later...If this will be anywhere near your kitchen you better not like to cook on your stovetop or toast bread. Also once it starts with the blaring loud beeping (there is a high pitched beep as well as low pitched one) and the voice and it does not stop. Once it has begun, it will go for well over the time it should. I had burned some toast and my neighbors came over to find out what was happening. Mind you there is over 110 ft between our houses. I am so bummed that I thought I was being super safe by buying this hardwired alarm as well as three battery operated that all connect. Once this one goes off - because OH NO, a pork chop is being cooked on the stovetop , all the other three start in with the same shreiking noise that puts all the animals into dire anxiety. THANKS FIRST ALERT!!! HOW FUN. Since this, I have bought 3 Kinde alarms for the bedrooms. This was a huge waste of money, UNLESS YOU SLEEP THOUGH A FREIGHT TRAIN IN YOUR LIVING ROOM AND BEDROOMS. Seriously OVER SAFE TO THE POINT OF NOT BEING SAFE. Does that make sense?
    6 people found this helpful
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    david l west
    5.0 out of 5 starsVerified Purchase
    Programming and Pairing can be tricky
    Reviewed in the United States on June 20, 2020
    Wireless Interconnect Pairing Instructions What are the steps to pair wireless interconnecting detectors to each other? Step 1: Pick a unit to be the “Teacher” • On that unit, simply open and close the battery drawer (if batteries are not installed, insert... See more
    Wireless Interconnect Pairing Instructions
    What are the steps to pair wireless interconnecting detectors to each other?
    Step 1: Pick a unit to be the “Teacher”
    • On that unit, simply open and close the battery drawer (if batteries are not installed, insert them at this time.)
    o This is all you do with this unit right now.
    Step 2: Prep the “Students”
    • On the units you want to connect (all the other detectors, minus the “Teacher”), while the drawer is open, press and hold test button and close drawer at the same time.
    o The light on the detector should be now blinking green.
    Step 3: Press and hold down the test button on the “Teacher”
    • You should then hear the other units (“Students”) chirp or start talking. This will indicate they are paired.
    Step 4: Press and hold the test button on any unit to test them.
    • If you paired them successfully, they should all start to test.
    o Make sure you hold the test button down until each chirp or say “Testing” (voice units only).
    To set location:

    SCO500, SA511, and CO511 units all have a voice feature. In order to change/set location, follow these steps:

    1. Open and close the battery drawer on the unit you want to set the location on.
    2. The unit will begin to talk and mention “To change location, press and hold test button now.”
    • At that moment, press down on the test button for about a second and let go. You should then hear the different location options. If you don’t, start from the beginning and try again.
    3. When you come to the location you would like to set, press and hold the test button down on that location.
    • If you miss the location you want, don’t worry. The options will continue to cycle through and back to the beginning.
    4. Once the new location has been set, the detector will notify you by saying “(Insert Location) location has been programmed.”

    Note:
    If you ever need to unpair your alarms, follow these steps to do so.

    1. Insert the batteries into the drawer of the alarm to be unlinked. DO NOT CLOSE THE DRAWER.
    2. Press and hold the test button while closing the battery drawer.
    3. Once you hear the unit chirp, release the test button. The green power LED will start to blink indicating the Wireless Alarm is waiting for program data.
    4. Press and hold the test button on the same alarm to unlink until the alarm chirps and its green power LED stops blinking. Then release the test button.
    5. This alarm is now unlinked.
    2 people found this helpful
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    NoShadowOfADoubt
    1.0 out of 5 starsVerified Purchase
    False alarms
    Reviewed in the United States on November 24, 2017
    I bought two from Amazon warehouse deals... which is a mistake because you cannot and shouldn''t save on safety. Besides that point, it gave false alarms ... one at 12 am and a second time during the day and it didn''t silence, and the second alarm didn''t silence the other... See more
    I bought two from Amazon warehouse deals... which is a mistake because you cannot and shouldn''t save on safety. Besides that point, it gave false alarms ... one at 12 am and a second time during the day and it didn''t silence, and the second alarm didn''t silence the other one. Also the model number that I received was SA520 not what it is shown here.
    15 people found this helpful
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    ASC2078
    5.0 out of 5 starsVerified Purchase
    Perfect Solution For My Detached Garage.
    Reviewed in the United States on February 8, 2021
    I recently built a detached garage, adjacent to my residence. While running the underground cables for this new garage, I forgot to run an extra signal wire to connect the smoke/CO2 alarms in the house to the ones in the new detached garage. If something happened in the... See more
    I recently built a detached garage, adjacent to my residence. While running the underground cables for this new garage, I forgot to run an extra signal wire to connect the smoke/CO2 alarms in the house to the ones in the new detached garage. If something happened in the detached garage, I wanted to hear it in the house too. After some research, I found these BRK/First Alert wireless bridge units. My required distance was within the 50 ft. range specified for this model. Fortunately, my other equipment was already BRK/First Alert. This made everything compatible with these wireless units. This wireless smoke detector also has the hard-wire connections to interface with both wired and wireless models. Once installed, two wireless units connected everything together in both structures. It was a great solution for the wire that I forgot to run. With the exception of being wireless, they function in the system, just like the other models. Note: I will offer A tip that I discovered by trial and error. After installation, I tried repeatedly to program and/or connect the signal of my two wireless units, per the instructions. After several unsuccessful attempts, I tried something different. I unplugged the two wireless detectors from their connections on the ceiling. I placed them on a table side by side and followed the programming instructions, using only their internal battery power. This worked perfectly the first time that I tried it. I then plugged the already programmed alarms, back in to their connections on the ceiling. The whole system worked great afterward. (See Attached Picture Diagram)
    One person found this helpful
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    Joe K
    5.0 out of 5 starsVerified Purchase
    Perfect solution to connect two hard-wired systems in my home
    Reviewed in the United States on October 11, 2016
    I added a new room to my house awhile back, and although I was able to add a hard-wire smoke detector to the room I could not connect it to the rest of my home. I initially installed a second detector hard-wired to the new room in a common area of the house so at least... See more
    I added a new room to my house awhile back, and although I was able to add a hard-wire smoke detector to the room I could not connect it to the rest of my home. I initially installed a second detector hard-wired to the new room in a common area of the house so at least those two were connected and smoke in the new room would alert the whole house. I wanted to fully correct the problem and bring the system up to code, and these smoke detectors were the perfect fix. I replaced the "new system" detector in the common area with the SA521CN and replaced one of the "old system" detectors with a SA521CN, followed the instructions to link them wirelessly, and now I have both systems fully connected. I tested various detectors throughout the house, and all of them activate whenever one is set off. Perfect solution for me; it would have cost me hundreds of dollars to hard-wire the two systems together.
    15 people found this helpful
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