My 1st thought, turn them on, 1 is better than none,and the $22.00 ea is worth every penny!
Do they go off at any particular time? or totaly random?
I have seen single units go bad and do this also.
are they ions or photo?(ions will have a "radio active mat" warning on the back)
If photos a good vacuume should help. If ion, most likely a bad unit. However kidde has a darn good product. so check with them.
Locations?
Ions are suseptable to air changes, steam etc, and are designed for a flash/high heat/quick change type event as well as smoke.Could they be near a register with a humidification unit?
Photos are best with smoldering types. The little light inside is very comfy for small insects.
The inter connect wire switches the neut.to the sounders.
a loose connection on any of the wires could do this.I've witnessed vibrations affect a device in the basement.
Are there heats on this circuit? I have seen the inter connect aux relay used for these fail and cause alarms.
Again, 2001, probably electronic heats, check any way.
Small water leak? anyway, get them working they do SAVE lives!
Just some thoughts, good luck
