Richard, The Smoke Alarm Doctor 15+ years in the fire alarm trade Updated November 2026

Kidde i12010S: lights, beeps & chirps explained

Hardwired ionization smoke alarm, sealed lithium backup (discontinued). Here is what every light and sound on the Kidde i12010S means, how to test and hush it, and when it needs replacing. It's an older model I still find on ceilings across the Lower Mainland.

Open it in the free app Book Online

Recall notice: After a power outage, affected alarms could get stuck in a mode where they would not sound for smoke or CO. Affected Canadian date codes: i12010S-CA 2014-03-11 to 2014-05-13; i12010S-CO-CA 2014-03-14 to 2014-05-13 (one more date code was added in 2015); KN-COSM-IBACA 2013-11-19 to 2014-05-13. The date code is on the back. Recall details.

An older model. Discontinued. Some 2014 Canadian units were recalled (see Recall check). Today's like-for-like replacement is the Kidde 20SA10-CA, which is photoelectric and has fewer nuisance alarms.

What the lights mean

Light	Meaning
Green, steady	Running on household power. Normal.
Green, flash every 60 s	Running on the backup battery only.
Green, flash every 2 s	Hush mode.
Green, flash every 16 s	Memory: this alarm went off earlier.
Red, flashing with the horn	SMOKE alarm.
Red flash + chirp every 60 s	Low battery. The battery is sealed: replace the alarm.
Red flash + chirp every 30 s	Unit error. Replace the alarm.
Red double flash + chirp every 30 s	End of life. Replace the alarm.

What the beeps and chirps mean

Sound	Meaning
3 long beeps, repeating	SMOKE. Get everyone out and call 911.
Chirp every 60 s	Low battery (sealed): replace the alarm.
Chirp every 30 s	Error or end of life: replace the alarm.

Want to hear them? The free app's sound library plays each pattern.

How to

Test it

Press the Test/Hush button. It should sound, then stop.

End of life

The end-of-life chirp can be silenced for about 3 days at a time, up to 30 days. Then it must be replaced.

How long does it last?

Replace it 10 years after the date printed on the back. The test button can still work after the sensor has worn out, so the date is what counts. Sometimes the date is on the side, but the back is the best place to look. Need one swapped? See smoke alarm replacement and repair.

What replaces it

Today's replacement is the Kidde 20SA10-CA ($69.99 installed, plus the $99.99 service fee).

Other alarm guides

Kidde 30CUA10-VCA · Kidde 30CUD10-CA · Kidde 20SA10-CA · Kidde 20SD10-CA · Kidde 900-0235 · Kidde i12010SCO · Kidde i12040ACA · Kidde 900-0220CA · Kidde P4010ACS

All alarm guides · Chirp codes: Kidde vs First Alert · Kidde smoke alarms in Vancouver

Questions

Why is my Kidde i12010S chirping?

Chirp every 60 s: Low battery (sealed): replace the alarm. Chirp every 30 s: Error or end of life: replace the alarm.

What does the green, steady light mean on the Kidde i12010S?

Running on household power. Normal.

How long does the Kidde i12010S last?

Replace it 10 years after the date of manufacture printed on the back.

What replaces the Kidde i12010S?

The Kidde 20SA10-CA. Hardwired photoelectric smoke alarm, 10-year sealed backup.