False Alarms on ELK-6052 Wireless Heat/Smoke Detector

[Thirdwaver]

Hey everyone,

We've been getting false alarms on our wireless smoke detectors and I'm at my wits end trying to understand what's happening. The system was installed by me in 2018. There are three wireless smoke detectors. They worked for some years with only one or two false alarms but they are getting annoying now. The alarm company suggested I clean them. I'm not positive that I'm doing it properly but I've attached a brush end to my vacuum and gone over them and begun doing that monthly now. Apparently didn't help since we had another false alarm this morning.

Some data:

1. They ALWAYS happen in the middle of the night. Never once had one during the daytime. Lucky me, but perhaps diagnostic.
2. It isn't always the same detector. Sometimes it's at the top of the stairs, other times in the rec room. Not sure I've ever had one in the primary bedroom.
3. There doesn't appear to be a correlation to the furnace. We keep it set pretty low at night. We had a false alarm at 4:12am this morning but according to nest history, the furnace didn't turn on until 6:45am.

Do these detectors expire? If so, is there a way to determine when? I'm getting ready to pull them out and put in regular non-connected detectors if I can't figure this out. Thanks for any experience or tips.