We've got hardwired Kidde photoelectric smoke alarms that randomly trip. Alarms are less than 4 yrs old, original wiring is 20 yrs old. We lived in our home several years before the issue surfaced and I replaced all the alarms in 2019 as the first solution. The replacements lasted about 6 months before it occurred again.

Typically they'll trip overnight and will only last one alarm cycle and turn off on their own. Occasionally they'll continue to cycle/alarm until I start unplugging them. I'm pretty sure I've narrowed down that unplugging the last alarm in the circuit will cause them to stop alarming.

Issue has been sporadic for several years. Sometimes will occur multiple times a month, sometimes we'll get a reprieve for 6+ months without issue.

Original smoke alarm circuit was tied into a general lighting circuit on a 15amp arc fault breaker. I've since split the circuit onto its own 15amp arc fault and still get nuisance trips. I've also added a whole home surge protecter on the main panel and still having issues.

Most recently, they've tripped once in August, once in October, and as of last night, back to back nights in November.

I've checked all the wiring and all the connections are tight. I'm calling an electrician this week. Just seeing if anyone else has had any issues remotely related to this and what their solution was.

I'm looking into the battery operated/wifi connected Nest smoke alarms but unsure if they'll meet NEC requirements.

Do them going off coincide with your heater coming on? I have had mine do that before and had to adjust the closest heating vents to direct them away from it.

It' occurs all year long. But along that thought, I've considered they were picking up dust/fuzz in the air.

We've implemented a monthly dusting/vacuuming of them to ensure that's not a problem. The randomness of it all is frustrating. After each fix we think of, we have to wait and see if it's been solved. It's a kick in the groin when there's 6+ months between alarms.