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First Alert smoke and carbon monoxide alarm error codes

First Alert smoke and carbon monoxide alarm indicators as First Alert lists them, each with its meaning and the first safe check.

A First Alert alarm that chirps is almost always signalling its own condition, and the pattern matters. A single chirp at regular intervals usually means the battery is low, a chirp after you have fitted a new battery can mean the battery is not seated or the alarm needs resetting, and a different, repeating pattern can mean the alarm has reached the end of its life or has a fault. A loud continuous siren is a real alarm: leave the house and call the emergency services.

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First Alert smoke and carbon monoxide alarm · exact signal

First Alert smoke and carbon monoxide alarm chirping a single chirp at regular intervals on a carbon monoxide alarm: meaning and exact next steps

chirping a single chirp at regular intervals on a carbon monoxide alarm means A maintenance chirp on a carbon monoxide alarm. First Alert says a weak battery is one of the most common reasons for a single chirp at regular intervals, and that many CO alarms chirp when they reach the end of their service life.

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First Alert smoke and carbon monoxide alarm chirping on a hardwired carbon monoxide alarm: meaning and exact next steps

chirping on a hardwired carbon monoxide alarm means A hardwired CO alarm chirping. First Alert says chirping can happen after a power outage, loose connection or electrical interruption, and that backup batteries can cause chirping if they are low or not installed properly.

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First Alert smoke and carbon monoxide alarm chirping on a hardwired smoke alarm: meaning and exact next steps

chirping on a hardwired smoke alarm means A hardwired issue. First Alert lists power surges, outages or loose wiring on AC-powered units among the causes of chirping.

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First Alert smoke and carbon monoxide alarm chirping on an older alarm: meaning and exact next steps

chirping on an older alarm means An expired alarm. First Alert says smoke alarms lose reliability after 10 years, and that a chirp on an older unit can be an end-of-life warning.

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First Alert smoke and carbon monoxide alarm chirping regularly, one chirp at a time: meaning and exact next steps

chirping regularly, one chirp at a time means A maintenance chirp rather than smoke detection. First Alert says low battery is the most frequent cause of regular single chirps, and that most units signal for replacement after 10 years of service.

Open record First Alert smoke and carbon monoxide alarm · exact signal

First Alert smoke and carbon monoxide alarm CO alarm chirping after a battery change: meaning and exact next steps

CO alarm chirping after a battery change means A CO alarm that still chirps with a fresh battery. First Alert lists: installed incorrectly, battery door not fully closed, needs a reset, at end of life, or a sensor or internal fault.

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First Alert smoke and carbon monoxide alarm smoke alarm chirping after a battery change: meaning and exact next steps

smoke alarm chirping after a battery change means A chirp that continues with a new battery. First Alert lists four things to check: battery polarity, the battery drawer not snapped completely shut, residual charge that needs a reset, and an expired unit.

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First Alert smoke and carbon monoxide alarm chirps

Check the label on the back of your alarm for the exact patterns, since First Alert uses different signals across models. Fit fresh batteries of the type shown, hold the test button until the alarm sounds and vacuum or wipe dust from the vents. Smoke alarms should be replaced about ten years after manufacture and carbon monoxide alarms on the schedule printed on them. Never remove a chirping alarm and leave the room unprotected; replace the battery or the unit.

First Alert sells smoke alarms, carbon monoxide alarms and combination units, and their chirp and beep patterns differ between them. Before you act on a pattern, check whether your unit is a smoke alarm, a carbon monoxide alarm or a combination, since the same number of beeps can mean different things. A smoke alarm that chirps once a minute usually needs a battery, a carbon monoxide alarm that chirps in a different rhythm may have reached the end of its life and an alarm that sounds continuously is signalling a real hazard. The guides on this page explain the chirps that First Alert publishes in its own guide, and they remind you that every alarm in the home should be replaced about ten years after it was made.

If you are unsure what a pattern means, replace the battery and test the alarm, and if the pattern continues, replace the alarm. A home with a working alarm in every sleeping area and on every level is far safer than one with a few old alarms, and the cost of a new alarm is small compared with the protection that it gives.

Why does my First Alert alarm chirp after a new battery?

The battery may not be seated fully or the alarm may need a reset. Reseat it and hold the test button until it sounds.

How old is too old for a smoke alarm?

Replace it about ten years after the manufacture date printed on the back.