How to Make the Flashing Green Light of a Carbon Monoxide Alarm Stop

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You may not be able to stop the flashing green light of a carbon monoxide alarm.
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Carbon monoxide alarms are an absolute necessity if you deal with any sort of natural gas heating or cooking methods. Carbon monoxide is known as a silent killer because there's no way to self-detect a leak that has no smell, taste or visible indicators. The best way to make sure you're safe is to install carbon monoxide alarms in your home that will go off if they detect any presence of this dangerous gas. The downside to these alarms is that they sometimes chirp or begin blinking red or green lights that can be a hassle to figure out and fix.


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Carbon Monoxide Alarm Indicators

The most obvious indicator that a carbon monoxide alarm has been set off is the piercing noise it makes when the gas is detected. However, the less obvious indicators, such as a blinking green or red light, can be more difficult to decipher.

It's important to keep in mind that all carbon monoxide units are different, depending on the brand and model you've purchased. In general, a steady or blinking green light isn't a cause for concern as long as the carbon monoxide alarm isn't chirping as well. The best way to know for sure is to refer to the user guide that came with the unit or to visit the manufacturer's website.


For example, First Alert has an LED light indicator chart on their website that covers what each light means for their various model numbers. A flashing green light can simply mean that the unit is installed and working properly. In this situation, you wouldn't want to stop the flashing green light.

Flashing Green Light Possibilities

If the light wasn't flashing before and it has recently started, you may need to reset the unit. If the blinking has begun due to a power outage, for instance, you need to locate and press the Test/Silence button or a similarly labeled button. Be warned that the unit will make a very loud piercing sound; however, after you've pressed the button, the light should stop flashing and return to its normal way of functioning.


Another reason the green light may begin to flash may be that it has been triggered by a light presence of carbon monoxide. In this case, the light will continue to flash until it has a reading under its accepted levels or the level of carbon monoxide rises, which will lead to the siren warning you that you're in danger due to a leak. This type of blinking green light can't be physically rectified as the unit is simply doing its job of detecting potential danger.


The flashing green light on a carbon monoxide alarm is unique to each model and brand, so it's important to check with the appropriate company or user guide to verify the meaning. A constantly flashing green light can mean nothing more than proper functioning if the light has always been there. This means that it would be impossible to rid the alarm of the flashing light completely. Note that if the green light is ever accompanied by any noises, including chirping, it may be that the battery or the unit itself needs to be replaced.


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