Why Is My Hard-Line Smoke Detector Beeping?

Change the Battery

• Hard-wired fire alarms have backup batteries that can cause the alarm to chirp. In the case of a hard-wired alarm, simply removing the battery will not usually solve the problem. It may actually make the chirping worse. Avoid this problem by replacing the battery every year when you reset your clock for daylight savings time. Most smoke alarms use a 9-volt battery that will last for up to a year. Some hard-wired smoke detectors may use a lithium battery that lasts longer. A few brands have batteries that are not changeable and you will need to replace the entire smoke detector.

Clean It

• Another cause of a chirping smoke detector is dirt or dust that gets inside the detector and clouds the receptor in the same way that smoke would. This is usually a problem in the kitchen where greasy exhaust from cooking can get into the detector, but it can happen anywhere. Over time the grease attracts dust and dirt, which obstructs the receptor. Spiderwebs and other debris can also get into the smoke detector and cause problems. Prevent this problem by giving the smoke detector an occasional swipe with the vacuum cleaner when you clean the ceiling fans, blinds or other items in the room. If the alarm is currently chirping, try blowing out dust and debris with a can of compressed air.

Power Outages or Surges

• A recent power outage or surge can cause hard-wired smoke detectors to chirp. This can also be caused by other appliances on the same circuit breaker starting up. Sometimes there are power fluctuations on the line that may not be detectable to you, but may cause the smoke detector to malfunction. In these cases, turn off the power at the breaker, remove the battery and press the reset button. Replace the battery and turn the power back on. You should hear a chirp when the unit powers up, but the constant chirping will stop.

Check the Room Temperature

• Some hard-wired smoke detectors are sensitive to temperature in the room. They will chirp if the room is extremely hot or cold. Usually, adjusting the room temperature will stop the chirping when this is the problem.

Carbon Monoxide Detectors

• Is it possible that the detector is a carbon monoxide detector, rather than a smoke detector? If the alarm is steady, more than just a signal beep, consider that there might be a carbon monoxide problem. Additionally, some carbon monoxide detectors will chirp with a warning signal when carbon monoxide begins to accumulate, then change to a continuous alarm as the problem intensifies. If you have a gas furnace or other potential sources of carbon monoxide, don't discount the possibility that this could be the problem. Carbon monoxide is deadly, so have your home checked out immediately.

Malfunctioning Smoke Alarm

• Occasionally, a smoke alarm will malfunction, causing it to chirp periodically. If you have tried everything and your smoke detector is still chirping, you will need to replace the smoke detector. Most smoke detectors need to be replaced every eight to 10 years. If your alarm is an old one, consider replacing it immediately.