SOLVED!! Why is Smoke Alarm Blinking Red

Is your Smoke Alarm Blinking Red? If yes. This might be a result of working normal operation or it’s a sign that you have some dust inside the smoke detector. 

If you are faced with this, you might be feel less bothered since you can’t perceive any smoke smell or something burning.

However, leaving it might not be a good choice because the red signal can become a new normal which can, in turn, make you less receptive to real situations of emergency when they arise.

That said, let’s find out the reason behind your smoke alarm blinking red light and what you should do about it.

Is your Smoke Alarm Blinking Red too?

Most smoke alarm brands have assigned what different light connotes and how you can figure out what a specific light means. This is usually based on the instruction in their manual.

Nonetheless, these probably vary across popular brands of smoke alarms since the difference is little.

That being said, I will be explaining the justifications for your smoke alarm blinking red light and what you should do about it.

 1. Low Batteries 

low battery

The time span of your smoke alarm battery is with 10-12 months. In a scenario where you have a low battery, you could encounter a red light blinking on your smoke alarm.

But, not all smoke alarm blinking red light connotes low battery, some smoke alarm might demarcate a low battery with a yellow blazing light.

However, if you are using a First Alert smoke alarm, it shouldn’t come as a surprise to you that it blinks red light for a low battery.

You can easily decipher this based on the time gap between each flash. If the red light signifies low batteries, the time gap between each flash is usually 20-30 seconds.

How to fix it

Since your smoke alarm battery is low here are the steps you should follow to replace it

  • Remove the battery compartment cover
  • Now, slide open the tray and take out the old batteries.
  • Avoid touching any of the electrical contacts inside the battery compartment while doing this
  • Finally, insert the new set of batteries just as the old ones were placed

NOTE: It is recommended to change the smoke alarm battery once every year

You should check here. for a comprehensive way to detect if your smoke alarm battery is low

2. After Effect of Smoke Alarm

Let’s say your smoke detector just perceived smoke probably from outside, and it starts blinking red then after some time it goes off. But then, you notice the smoke alarm blinking red light all over again

Once you notice this, all you have to do is to allow air ventilation in your room, especially where the smoke alarm is located to allow fresh air to circulate since there might still be some smoke lunging in the room.

3. The Smoke Alarm is Working As it is Supposed to

Similarly as examined before, a green light connotes that the smoke alarm is working appropriately, while in a few different brands of smoke alarms it means danger.

It’s hard figuring this out, however, one great pointer is the delay between each smoke alarm red light flick.

Once, the room is free of burning smell, or the smoke alarm isn’t ringing, then, there is no need to overreact.

4. The Smoke Detector is Almost Expired

the smoke alarm is working normally

A smoke Alarm would normally last for 10 years. So you don’t need to worry about a replacement for a while. 

But as it begins to close in on its shelf life the smoke alarm may begin to malfunction. One of the things you may easily notice is the frequent red flashing light and the rate at which the battery last 

That is one of the reasons why it is advisable to replace the smoke detector before its gets to the expiry date 

5. Presence of Dust  

Your smoke alarm also detects dust and would flash a red light once the dust gets too much. This is one thing you need to be aware of since you might feel the smoke alarm only reacts to smoke which isn’t totally true

However when you notice this, then it is a good pointer that you need to clean your smoke detector probably some dust has gathered inside the device.

If you are unsure of how to do that follow the steps below

  • Remove the chamber from the smoke detector.
  • Next, use a lint-free cloth to wipe the chambers 
  • Next, use a vacuum to blow out any dust/dirt in your smoke detector

6. A smoke Alarm Detects Smoke

Smoke Alarm Blinking Red

A smoke alarm blinking red light very rapidly coupled with a visible alarm sound is a dangerous sign. It basically signifies that the smoke alarm has detected smoke or a burning smell

The smoke from fires is dangerous to human health since it produces carbon dioxide which is harmful to humans after continuous exposure to it. So it is safe to say If you notice any smoke or burning fire. Abort your house and immediately call security operatives.

How to Turn off Red light on Smoke Detector

There are different ways to turn off the red light of your smoke alarm if it has been blinking red light for a while. You can either reset the smoke detector or change its batteries so as to clear out any error on it 

To carry out a reset, you can check here for a comprehensive guide on how to reset a smoke detector

Smoke Alarm Red Light Flashing every 10 Seconds

In a scenario where your smoke alarm flashes red light after every 10 seconds. It is doing that as the after effect of smoke after effect. All these simply mean the 10 seconds blink signifies that the smoke detector is in a desensitized state.

Red Light Flashing on Smoke Alarm after Changing Battery

After changing the batteries of your smoke Alarm detector, the smoke alarm blinking red would be cleared out making it return to a normal working state, however, if it blinks red light after this, it simply means it is working perfectly.

But if it continues for too long, then reset will clear out any issues.

Smoke Alarm Greenlight

A green light signifies that the batteries are low. Also, it could signify a unit in a series of interconnected alarms is blinking. What this light signifies is based on the brand and all these things are usually found on the device manual so as not to have any further confusion.

Recommended: How to fix Smoke detector blinking greenlight

How to Reset the Smoke Alarm Detector?

Before you reset your Smoke detector you have to do some checking to it to ensure you are approaching the right problem with the right solution. That said, here is how you can reset your smoke detector.

NB: The test instruction is always on the user manual since the reset procedure slightly varies based on the brand

That said, here is how you reset your smoke detector

  • Locate the test button
  • Push and hold the button on your device for around 5 seconds till you hear a beep sound. In some instances, you will hear a series of beeps.

If your smoke detector is always beeping and chirping check here for a comprehensive guide to resolve that.

Smoke Alarm Yellow Light

A yellow light usually means that your smoke detector battery is low and needs a replacement. While in some other cases, it could mean that the device is reaching the end of its life and needs a replacement.

Smoke Alarm Red light with no sound

There is no cause for alarm if your smoke detector is giving out a red light since it simply means the detector is receiving power. it is common with hard-wired smoke detectors.

Why is my Smoke Alarm Red light flashing every 20 seconds?

You could experience this due to the after effect of smoke or a low battery, but then, a low battery is a popular culprit as to why this is happening. But, the smoke alarm blinking red light is synonymous with the first alert smoke detector.


The Smoke alarm blinking red light could be a dangerous signal or it could be a result of a low battery, but then, you should always take the red light series and ensure that the batteries are replaced once a year while the smoke detector is changed before it expires.

You don’t want a dangerous signal to appear as a new normal due to negligence.

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