If the unit is seven years old, and the red or green LED's are flashing in sequence with the intermittent chirping you're encountering, this is the end-of-life signal that Kidde builds in to all their units. You'll have to replace it. If, however, it's just the chirping that's concerning you, this is likely the low battery alert. To change the unit, remove it from the wall (or the base if it's ceiling mounted). In the latter case, you'll notice a wiring harness plugged into the back. You'll have to squeeze the two tabs on either side of the plug together to remove it. Take out the old battery. Leave the unit UNPOWERED for five minutes. This will reset the low battery circuit. While you're waiting, clean the unit thorougly using the soft brush attachment on your vacuum. Do not blow compressed air through the sensor. Insert new high quality alkaline batteries (Duracel or Energizer) and depress and hold the test button to ensure it responds appropriately. Plug the unit back in and reinstall it on its base. You're done!
I don't think the unit is any where near 7 years old, but yes, its the chirping thats concerning. What does it do when there is actual carbon monoxide detected in the air? How is the chirpng different? and how do I know it is safe in the house? I have all the windows open now.
The alarm will be continuous. You have a low battery warning. Nothing to be concerned about. You can download the manual for yourXXX@XXXXXX.XXX dot com. Close your windows. Replace the batteries and you'll be okay.
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