First alert fire alarm red light

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First alert fire alarm red light. First Alert Strobe Light SLED177 * California and New York Residents - Please note this alarm is not compliant with your State's 10 Year Sealed Battery Alarm Legislation Requirements. ... First Alert Dual Sensor 10-Year Battery Smoke and Fire Alarm - SA3210 . MPN: 1039842 (56) $56.95 Save: $23.00 Quick view First Alert Basic Battery …

alarms it will also provide hearing impaired individuals with a visual and audible warning of a carbon monoxide danger. Please take the time to read this manual and make this Smoke and Strobe Light Combo Alarm an integral part of your family’s safety plan. Key Features: Low Profile Design: Half the size of a standard alarm 177 Candela LED ...

Power Source: Battery Operated. Battery Type: Two AA. Sensor: Photoelectric and Ionization. Optipath 360° Technology: Patented technology provides 360° of direct access to the smoke sensor. Intelligent Sensing Technology: Helps reduce nuisance alarms. Noise Output: 85 dB in a T3 Pattern. Single Button: One press to silence and test alarm. AC and AC/DC units will have a power indicator light (red or green) that shines when they are receiving electrical power. If you have a 10-year model, the smoke alarm may not have been properly activated. If the tab broke away before the alarm was activated, you can use a toothpick to move the switch over to test the alarm. This Smoke Alarm must have AC or battery power to operate. If the AC power fails, battery back-up will allow the alarm to sound for at least 4 minutes. If AC power fails and the battery is weak, protection should last for up to 7 days. If AC power fails and the battery is dead or missing, the alarm cannot operate.1. Low battery: One of the most common causes for a blinking red light is a low battery. This can be applicable to various devices such as remote controls, smoke detectors, and wireless headphones. When the battery power drops below a certain level, the device may indicate it by blinking a red light. 2. 1039862 Combination Smoke and CO Alarm with 10-Year Battery & Voice Alerts Luckily, if your First Alert carbon monoxide alarm is holding a steady red light, this means that it is operating normally. However, I do understand the uncertainty since red lights typically indicate that something is wrong. Having a working carbon monoxide alarm can sometimes lower your homeowners insurance premium and is …Below-mentioned points are the common reasons why your smoke detector is blinking red. 1. The Smoke detector has Low battery power. When you see a red LED light blinking in your smoking detector with a chirping sound, it indicates the low battery power. In this case, the red light blinks every 60 seconds. 1. Batteries are Low. Many First Alert smoke detectors have an LED light, which blinks red when the batteries need to be changed. In addition, a chirping or beeping noise may be heard. However, the blinking light is your only indication that you need to replace the fire alarm’s batteries.

The First Alert SC7010B Combination Smoke and Carbon Monoxide Alarm uses an advanced electrochemical CO sensor to detect elevated carbon monoxide levels from a variety of sources, such as faulty fuel-burning appliances, blocked chimneys, and cars left running in the garage. The hardwired alarm is also microprocessor-controlled to help …What does it mean? This is the power indicator light: First Alert and BRK alarms have a power indicator light to show you that your alarm is receiving power. Some alarms …How to Install RM4. To install this relay to an alarm, connect the power wires as listed below. See diagrams for connections. Note: If wiring the relay remote from the alarm, use a maximum of 1000 feet [300 meters] of #18AWG or larger wire rated at least 300V. Alarm.TCE is a simple, web-based service for Fire Prevention Bureaus to track and drive code compliance, reduce false alarm activity, and provide safer communities through third …Why Is The Red Light Blinking On My First Alert? The red light blinking on your First Alert fire alarm could indicate that it’s time to test the alarm again or that the batteries are low. Consider adding fresh batteries and running a test to ensure that it’s working properly. If you have a carbon monoxide alarm, the red light flashing means ...

It is important to know the difference between the beeps or chirps. Refer to your alarm's user manual for your specific model. 4 beeps and a pause: This means that there is carbon monoxide in the air and you should seek fresh air immediately and call 9-1-1. 1 beep every minute: This means that the detector has low batteries and you should ...First alert smoke alarm - fire smoke detector user manual (8 pages) Smoke Alarm First Alert 9120 User Manual. ... /Silence Button: Press and hold to activate test, or to silence the alarm. 2. POWER Light (GREEN)/ SMOKE ALARM Light (RED) 3. CO ALARM Light (RED) 4. Battery Drawer 5. (Behind the Cover) Alarm Horn: 85dB audible alarm for test ...We are a professional alarm company, that specializes in providing do-it-yourself interactive security solutions. Our commitment to research and development helps ensure that our …SKU: 1046747. WHERE TO BUY. Illuminate your path to safety with the First Alert SM210L Sealed 10-Year Battery Smoke Alarm with Safety Path Light. The SM210L smoke alarm also features First Alert's Precision Detection advanced sensing technology and meets new industry standards. The 10-year battery means no battery replacements for a decade.Immediately evacuate the building to fresh air and safety. Call 9-1-1 once safely outside to report the incident and if there is anyone experiencing carbon monoxide poisoning symptoms like headaches, dizziness and vomiting. Do not return into the building until it has been cleared by first responders. Even if your alarm stops alerting, and you ...Model 9120B. with 10 year Battery Backup. Printed in Mexico. M08-0134-010 K1 . Model. 9120B. 01/15. CONFORMS TO. UL STD 217. IMPORTANT! PLEASE READ CAREFULLY AND SAVE. This user’s manual contains important information about your Smoke Alarm’s operation.

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1 How to Install this Smoke Alarm. 2 Optional Locking Features. 3 Regular Maintenance. 4 If this Smoke Alarm Sounds. 5 Understanding the Indicator Lights and Alarm Horn Patterns. 6 Weekly Testing. 7 Latching Feature. Download this manual. Original version. On First Alert® carbon monoxide alarms, the red light flashes to show the Carbon Monoxide Alarm is properly receiving battery power. If you do not see the red light flashing, change the batteries in the alarm immediately. 1. Open any page in the Help Center. 2. Click the search icon in the top right corner. 3. Input your model number and select your product. 4. Click Download product manual.Learn how long alarms last when they haven't been activated yet. Install a Battery-Powered First Alert Alarm. Learn the step-by-step process for installing a battery powered alarm. Photoelectric vs Ionization Smoke Alarms.If you notice a blinking green light and your fire alarm chirping or beeping intermittently, it’s a sign that the battery needs to be changed. 3. Malfunction: If your fire alarm is blinking green, it could also be a sign of a malfunction. This can happen when there is an issue with the wiring, sensors, or other components of the alarm.When there is a high carbon monoxide level, a CO alarm will beep four (4) times in a loud, repeating pattern and the “move to fresh air” light will blink along with the alarm. The phrase "move to fresh air" is printed on the …

A low battery light and chirp sound will let you know when the batteries need to be replaced. A one-touch button silences false alarms and allows you to test ...First Alert is the most trusted brand in fire safety. We offer a variety of smoke alarms, carbon monoxide (CO) detectors and combination smoke & CO alarms to help provide you peace of mind knowing your home and loved ones are protected. Smoke Alarms. Smoke alarms help provide an early warning in the event of a fire emergency.Remove The Battery: First, you will be needing to take out the old batteries to reset both the smoke alarm and the red light. Take out the outer casing and find the battery tray, and then you will find a lever, pop the lever to open the battery tray. After that, remove the old battery from the smoke detector.Below-mentioned points are the common reasons why your smoke detector is blinking red. 1. The Smoke detector has Low battery power. When you see a red LED light blinking in your smoking detector with a chirping sound, it indicates the low battery power. In this case, the red light blinks every 60 seconds.Luckily, if your First Alert carbon monoxide alarm is holding a steady red light, this means that it is operating normally. However, I do understand the uncertainty since red lights typically indicate that something is wrong. Having a working carbon monoxide alarm can sometimes lower your homeowners insurance premium and is …First Alert smoke alarms are designed to alert you and your family to the presence of smoke in your home. Carbon monoxide (CO) alarms alert you to unwanted and potentially deadly levels of CO. Unlike smoke, carbon monoxide is a colorless, odorless, tasteless gas, which makes a detection device essential for the health and safety of people and ...View and Download First Alert 0827 user manual online. SMOKE ALARM WITH TEN-YEAR NON-REPLACEABLE LITHIUM BATTERY PACK AND END OF LIFE NOTIFICATION FEATURE. 0827 smoke alarm pdf manual download.The First Alert 0827 Sealed Ionization Smoke Alarm features a 10-year sealed lithium battery, eliminating the need for battery replacements during the lifetime of the alarm. This fire detector with ionization sensor has a tamperproof design, a mute feature, a power LED and alarm indicator, end of life warning, and single test button. Includes ...A. Some signs that a First Alert carbon monoxide detector may not be working include a beeping or chirping sound, a yellow or red light indicator, or if the device is not responding to the test button. These signs may indicate a low battery, end of life, or a malfunction. AC and AC/DC units will have a power indicator light (red or green) that shines when they are receiving electrical power. If you have a 10-year model, the smoke alarm may not have been properly activated. If the tab broke away before the alarm was activated, you can use a toothpick to move the switch over to test the alarm.

If you suspect an actual fire – Never take chances with smoke detector alarms – call 911 or the fire department immediately if you suspect real smoke or fire. If unsure about the cause of the alarm – When in doubt about the reason for frequent false alarms, the fire department can inspect the device and diagnose issues. Safety first ...

Activate the lithium battery back-up by removing the "Pull to Activate Battery Back-Up" tab. Push and hold Test button until the alarm sounds: 3 beeps, pause, 3 beeps, pause. Using wire nuts, connect the power connector to the household wiring. Plug the power connector into the back of the Smoke Alarm.Below-mentioned points are the common reasons why your smoke detector is blinking red. 1. The Smoke detector has Low battery power. When you see a red LED light blinking in your smoking detector with a chirping sound, it indicates the low battery power. In this case, the red light blinks every 60 seconds.A fire alarm system serves many functions and the differences between the functions can be a bit confusing, so I created a visual guide to fire alarm basics. The objective of this blog series is to discuss some of the major components and functions of a fire alarm system. On First Alert® carbon monoxide alarms, the red light flashes to show the Carbon Monoxide Alarm is properly receiving battery power. If you do not see the red light flashing, change the batteries in the alarm immediately. When there is a high carbon monoxide level, a CO alarm will beep four (4) times in a loud, repeating pattern and the “move to fresh air” light will blink ...120-volt hardwired smoke alarm wires directly into your home's electrical system. Ionization smoke sensor reliably detects particles from fast-flaming fires. Can integrate with up to 12 other First Alert or BRK hardwired smoke detectors. Easy-to-access battery compartment; 9-volt battery included. Hassle-free installation, no need to rewire.Here are five popular smoke detectors and their red light meaning: First Alert SA320CN: The solid red light on this model indicates that the smoke detector is receiving power and functioning properly. Kidde KN-COSM-IBA: A red light not blinking indicates a fault within the device, such as a faulty sensor or electronic component.This means that carbon monoxide has been detected in the area, you should move to fresh air and call 9-1-1. 1 Beep Every Minute: Low Battery. It is time to replace the batteries in your carbon monoxide detector. 5 Beeps Every Minute: End of Life. This type of chirp indicates it is time to replace your carbon monoxide alarm.Power indicator and night light. Blue: N/A : Unit is in pairing mode, and ready to connect to your mobile device. “This is only a test. The alarm will sound and for your protection is very loud. The test will start in 5 seconds. 5, 4, 3, 2, 1.” The unit’s test mode has been is activated and is about to alarm. Blue pulsing "Bluetooth mode."Low Battery: This is the most common reason for chirping smoke alarms. It's usually a single beep at intervals of 30 to 60 seconds. Replacing the batteries with fresh ones should silence the alarm. End of Life: Smoke alarms don't last forever. If your smoke detector is chirping constantly or in a different pattern than usual, it may be nearing ...

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Page 1 Position the base of the Smoke Alarm over the mounting bracket and turn. The Fire Department for detailed fire protection requirements in buildings not defined as Alarm Models 9120B, SC6120B, SC9120B, 7010B, SC7010B, SC7010BV, 100S, 4120, rechargeable batteries. Clean the battery contacts and also those of the device Always discharge the ...Before you reach for your alarm, first make sure there is not a fire or danger in the area. Whether the smoke detector went off because you burnt something in the oven or because there is an actual fire present, you need to be certain that your environment is safe. After that, you can reset your alarm, especially when it has not stopped ...Install a Battery-Powered First Alert Alarm. Learn the step-by-step process for installing a battery powered alarm. ... First Alert Consumer Support. Hours of Operation: Mon-Fri (9am - 8pm CT) Sat-Sun (9am - 5:30pm CT) 1-800-323-9005. Onelink & Smart Home Support. Hours of Operation: Mon - Fri (9am - 8pm CT) Sat - Sun (9am - 5:30pm CT) 1-833 ... It is important to know the difference between the beeps or chirps. Refer to your alarm's user manual for your specific model. 4 beeps and a pause: This means that there is carbon monoxide in the air and you should seek fresh air immediately and call 9-1-1. 1 beep every minute: This means that the detector has low batteries and you should ... A 36-year-old US citizen has pleaded guilty to conspiring to smuggle over $250,000 (£200,000) worth of sensitive drone technology to Russia, the US Department … This type of chirp means that smoke has been detected in your home. You and your family need to evacuate and call 9-1-1 once safely outside. Low Battery or End-of-Life: This type of chirp indicates it is time to replace your smoke alarm's batteries or the smoke alarm itself. Refer to your smoke alarm's user manual for the specific beeps based ... Help protect your home with the First Alert P1200A Slim Battery-Operated Photoelectric Smoke Alarm. This low-profile smoke alarm uses an ultra-reliable photoelectric sensor to detect smoke from slow-burning, smoldering fires. Half as thick as a standard alarm, this detector has a slim, contemporary design that mounts unobtrusively on a wall or ...Dec 13, 2023 · After replacing the battery in your fire alarm, encountering a blinking red light might be perplexing. Several factors could contribute to this unexpected behavior, including: A. Improper Battery Installation: Incorrect Orientation: The battery might have been inserted incorrectly, leading to improper contact and triggering a fault signal. Nov 28, 2023 · A blinking red light on a First Alert Smoke Alarm typically signals that the device is functioning properly; nonetheless, it’s critical to adhere to specific cleaning and care practices to prevent false alarms. Dust and debris can easily interfere with the sensors, so a gentle vacuuming using a soft brush attachment or blowing compressed air ... Fire ants are red-colored insects. A sting from a fire ant delivers a harmful substance, called venom, into your skin. Fire ants are red-colored insects. A sting from a fire ant de... ….

Are you an employee? Login here. LoadingIt is important to know the difference between the beeps or chirps. Refer to your alarm's user manual for your specific model. 4 beeps and a pause: This means that there is carbon monoxide in the air and you should seek fresh air immediately and call 9-1-1. 1 beep every minute: This means that the detector has low batteries and you should ...Learn what to do if your smoke alarm is chirping even after you install new batteries. About our 10-Year Battery Alarms Learn about 10-year-battery alarms offered by First Alert and BRK.Learn what to do if your smoke alarm is chirping even after you install new batteries. About our 10-Year Battery Alarms Learn about 10-year-battery alarms offered by First Alert and BRK.Push and hold the Test/Silence button on the cover until you hear an acknowledge "chirp". The alarm horn will sound 4 beeps, a pause, then 4 beeps. The ALARM (RED) light will flash. The alarm sequence should last 5-6 seconds. If it does not alarm, make sure the battery is correctly installed, and test it again. TO MOUNT ON THE WALL. Tools you ...AC Powered Photoelectric Smoke & Strobe Light Combo Alarm Model 7010BSL. Input: 120V AC ~, 60Hz Electrical Rating: 0.05A Standby, 0.60A Alarm Voltage Rating: Special Application 108–132 VAC. Make sure the Alarm is not receiving excessively noisy power. Examples of noisy power could be major appliances on the same circuit, power from a ...Thak You. The First Alert P900E Smoke and Fire Alarm provides maximum protection and has a new sleek, slimmer design, which adds an element of style to safety. The P900E has a modern, thin square design that’s less than an inch thick (half the size of a standard alarm), while still providing all the protection you need to keep what matters ...Remove the smoke alarm from the mounting bracket and disconnect the power. Remove the battery (for a sealed-battery model, see Battery Settings for a 10-Year Alarm to learn more). Press and hold the test button for five seconds. Reconnect the power and reinstall the battery. NOTE: The unit will chirp once when the power is restored, but should ...Reset. If the red blinking light on your first alert smoke alarm is flashing nonstop, it could be a sign of something more serious. This could be a power outage, low battery, or a weak or missing signal. If it’s a battery-powered device, changing the batteries should fix the problem. Most smoke detectors emit a low-battery chirp or beep and ...No, a blinking green light on a First Alert smoke detector means nothing serious. Blinking green light is part of its normal programming procedure which can happen in three circumstances- ... Three beeps on a First Alert alarm indicate that it has detected smoke in your home. Designed to alert you to potential fire or smoke hazards, this ... First alert fire alarm red light, If your carbon monoxide alarm keeps chirping, the battery may be low or weak. On First Alert carbon monoxide detectors, check to see if the battery light is yellow or green. If the alarm is chirping and the light is yellow, it means the battery is low. The way to get a carbon monoxide alarm to stop chirping is to replace the battery., Let’s start by discussing some of the possible causes of a First Alert Smoke Alarm that keeps going off. 1. Accumulation of Dust and Dirt. In most cases, you would be dealing with the buildup of dust and dirt inside the device. This is one of the most common reasons for smoke alarm malfunctions. With time, dust and dirt will accumulate on the ..., If your carbon monoxide alarm keeps chirping, the battery may be low or weak. On First Alert carbon monoxide detectors, check to see if the battery light is yellow or green. If the alarm is chirping and the light is yellow, it means the battery is low. The way to get a carbon monoxide alarm to stop chirping is to replace the battery. , The First Alert SC9120B Hardwired Combination Smoke and Carbon Monoxide Alarm is a hardwire alarm with battery backup. The hardwired detector includes a 9-volt battery backup for continued function in the event of a power outage. This combination fire and CO detector features a test/silence button and tamper-resistant locking brackets., Fire alarms are an essential safety feature in any home or commercial building. They provide early detection of smoke and fire, allowing occupants to evacuate quickly and preventin..., Bizarre lawsuit alert: The security firm (which still exists, apparently) is demanding that Rockstar Games pay it for using its name in Red Dead Redemption 2. Who could forget the ..., Bizarre lawsuit alert: The security firm (which still exists, apparently) is demanding that Rockstar Games pay it for using its name in Red Dead Redemption 2. Who could forget the ..., 4. Using a 3/16” (5 mm) drill bit, drill a hole through the center of the oval outlines you traced. 5. Insert the plastic screw anchors (in the plastic bag with screws) into the holes. …, A smoke alarm on a wall near a light. Slim Profile Smoke Alarm. This smoke alarm has a 10-year sealed battery, which means no battery replacements for the ..., Activate the lithium battery back-up by removing the "Pull to Activate Battery Back-Up" tab. Push and hold Test button until the alarm sounds: 3 beeps, pause, 3 beeps, pause. Using wire nuts, connect the power connector to the household wiring. Plug the power connector into the back of the Smoke Alarm., The First Alert 0827 Sealed Ionization Smoke Alarm features a 10-year sealed lithium battery, eliminating the need for battery replacements during the lifetime of the alarm. This fire detector with ionization sensor has a tamperproof design, a mute feature, a power LED and alarm indicator, end of life warning, and single test button. Includes ..., Here are some examples of why smoke detectors periodically have a flashing red or green LED light without an alarm sounding; To indicate that the alarm is receiving power and is operating normally. An end-of-life or low-battery warning. To indicate the alarm is in hush mode or that there is a fault with the alarm., Power Source: Battery Operated. Battery Type: Two AA. Sensor: Photoelectric and Ionization. Optipath 360° Technology: Patented technology provides 360° of direct access to the smoke sensor. Intelligent Sensing Technology: Helps reduce nuisance alarms. Noise Output: 85 dB in a T3 Pattern. Single Button: One press to silence and test alarm., A fire alarm beeping every 30 seconds is almost always caused by a low backup battery that powers the alarm in case of electrical failure. Follow this process to stop the beeps: Press the alarm test button to confirm it still works. Note whether a …, The battery-operated combination smoke and carbon monoxide alarm installs in minutes. The detector requires two AA batteries, and features a chirp and indicator light to let you know when they need replacing. The combination alarm mounts easily to a ceiling or wall, and comes with pins to secure alarm to the base to prevent tampering., The First Alert 0827 Sealed Ionization Smoke Alarm features a 10-year sealed lithium battery, eliminating the need for battery replacements during the lifetime of the alarm. This fire detector with ionization sensor has a tamperproof design, a mute feature, a power LED and alarm indicator, end of life warning, and single test button. Includes ..., Dec 13, 2023 · After replacing the battery in your fire alarm, encountering a blinking red light might be perplexing. Several factors could contribute to this unexpected behavior, including: A. Improper Battery Installation: Incorrect Orientation: The battery might have been inserted incorrectly, leading to improper contact and triggering a fault signal. , It is important to know the difference between the beeps or chirps. Refer to your alarm's user manual for your specific model. 4 beeps and a pause: This means that there is carbon monoxide in the air and you should seek fresh air immediately and call 9-1-1. 1 beep every minute: This means that the detector has low batteries and you should ..., Gently vacuum smoke alarms regularly using the soft brush attachment. Be sure electricians install the provided dust cover to keep alarm clean during construction. Insects covered or clogged the sensor chamber. Clean the smoke alarm with the soft brush attachment on your vacuum. Alarm was triggered from another part of the home., First Alert fire safety products, smoke, and carbon monoxide alarm systems for the home can be purchased at the First Alert Store Online or at the retailers like Amazon, Lowe's and more. ... FE1A10GOA Rechargeable Home Fire Extinguisher UL Rated 1-A:10-B:C (Red) Suppressants; More Safety Products ..., Resetting the smoke alarm will stop the noise. Follow these easy steps to reset your First Alert smoke alarm. Remove your First Alert smoke alarm from its position on your wall or ceiling. Carefully open the cover and remove the batteries. Long press (15-30 seconds), then release the Test button., 1 How to Install this Smoke Alarm. 2 Optional Locking Features. 3 Regular Maintenance. 4 If this Smoke Alarm Sounds. 5 Understanding the Indicator Lights and Alarm Horn Patterns. 6 Weekly Testing. 7 Latching Feature. Download this manual. Original version. , 3 Beeps and a Pause: EMERGENCY. This type of chirp means that smoke has been detected in your home. You and your family need to evacuate and call 9-1-1 once safely …, Dust Covers for Smoke, CO, or Heat Alarms. Learn how dust covers can protect alarms during remodeling or painting. Remove an Alarm from the Ceiling or Wall. Learn how to remove a First Alert smoke, CO, or combo smoke/CO alarm from its mounting bracket., THE COVER OF YOUR SMOKE/CO ALARM 1. Test/Silence Button: Press and hold to activate test, or to silence the alarm. 2. POWER Light (GREEN)/ SMOKE ALARM Light (RED) 3. CO ALARM Light (RED) 4. Battery Drawer 5. (Behind the Cover) Alarm Horn: 85dB audible alarm for test, alarm, and unit malfunction warning. Page 7: Smart Interconnect" Feature , First Alert smoke detectors are a crucial component of home safety, providing early warning in the event of a fire. However, homeowners may occasionally experience false alarms or ..., Install a Battery-Powered First Alert Alarm. Learn the step-by-step process for installing a battery powered alarm. Photoelectric vs Ionization Smoke Alarms. ... First Alert …, Subscribe and help me reach 10 000 subs ️. Thank you for your support 🙏Step by step installation. Products used in this video:Smoke Alarm, Battery - https:..., 1. Low battery: One of the most common causes for a blinking red light is a low battery. This can be applicable to various devices such as remote controls, smoke detectors, and wireless headphones. When the battery power drops below a certain level, the device may indicate it by blinking a red light. 2., 7020BSL. User manual. First Alert 7020BSL User Manual. Ac powered slim line smoke & strobe light combo alarm with sealed lithium battery backup. Also See for 7020BSL: …, To find the initiating unit you must look for the alarm with a fast blinking light while the alarms are sounding. If the event stops before the alarm is found, you can use the latch feature to find out which alarm was triggered. Latching Alarm Indication – Alarm Latch and Low Battery Latch Certain Interconnect alarms have a Latching Alarm ..., View the First Alert 9120B manual for free or ask your question to other First Alert 9120B owners. Manua. ls. ... A Smoke Alarm can help alert you to fire, giving you precious time to. escape. ... When I got up to check the unit, I found the green light flashing on and off. I got the ladder and pressed the test button. The green light became ..., It is important because a faulty fire alarm can lead to massive fires. If you have an ionization detector built into your smoke detector, the red light indicates that it needs to be replaced. Ionization detectors are more sensitive and will activate earlier than photoelectric detectors when exposed to smoke or fire.