Kidde 900-0220CA: lights, beeps & chirps explained
Battery-powered smoke + CO combo with voice (KN-COSM-BACA), 2 × AA. Here is what every light and sound on the Kidde 900-0220CA 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. For carbon monoxide protection, see our carbon monoxide alarm installation.
What the lights mean
| Light | Meaning |
|---|---|
| Red, flashing with the alarm | Smoke or CO detected. |
What the beeps and chirps mean
| Sound | Meaning |
|---|---|
| 3 long beeps, repeating | SMOKE. Get everyone out and call 911. |
| 4 short beeps + "Warning! Carbon monoxide!" | CARBON MONOXIDE. Get into fresh air and call 911. |
| Beep + "Low battery" | Replace both AA batteries. |
Want to hear them? The free app's sound library plays each pattern.
How to
Battery
Uses 2 × AA batteries. Replace both together.
Check the label
900-0220 is the part number; the model on the label reads KN-COSM-BACA.
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 30CUD10-CA ($89.99 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 i12010S · Kidde i12010SCO · Kidde i12040ACA · Kidde P4010ACS
All alarm guides · Chirp codes: Kidde vs First Alert · Kidde smoke alarms in Vancouver