That happened to us a bit back. We decided to replace our old alarms. I pulled one down, so I could look up the model number and discovered they had been recalled a few months after they had been installed. One week later, we had all new smoke/CO alarms. The annoying bit was, while the baseplates were the same, the connectors were completely different. Luckily, Mrs Magill and I have wiring experience.
Oh, and speaking of calling the non-emergency number. About five years ago, the smoke alarms went off while Mrs Magill and I were out on our bikes. My son called me and told me. I told him to get himself, his brothers, and the rabbit out of the house, and I rode like the wind the five miles back home. When I got home, it was reported to me that, while the alarms were going off, none of the sprinklers activated, so there was likely no fire. My oldest and I grabbed the extinguishers, and went room to room, feeling any closed doors. We didn’t find anything. I went outside and called the non-emergency number and told them that one of our smoke alarms was malfunctioning, and I did not have the expertise to find it. She said she’d send someone around. Five minutes later, two trucks showed up with lights and sirens on. Eight guys had come. They found the offending alarm and removed it. They then told me I didn’t need to worry about replacing it because there were two others within six feet of it.