In ,
typed:
Went back to the condo and pushed the test button, Nothing.

Went to Menards and bought 4 new Kidde replacements.

I will try to get them in this weekend.
After replacement I will test and check with the neighbors to see if
there units alert and post a follow up.

Thanks

Since you have FireX now, you may want to consider returning the Kidde
detectors to Menard's and buying FireX replacement detectors.

As far as I can tell, replacing FireX detectors with Kidde detectors may
involve having to use the "adapter" that comes with the Kidde models etc:


https://www.youtube.com/watch?v=GeQ3BsXAWp8



My inclination would be to keep the same brand as the originals.