Bests & Worsts Reviews from Amazon

I bought this 4 years ago. Put it in the walk-in closet where we sometimes put our baby down to sleep in the basement and basically forgot it was there, with the exception of occasionally wondering if it really does work. Well....this week we found out. The alarm went off in the morning, I pushed the reset button to turn it off (I appreciate that there is a different beeping pattern to indicate low battery vs. dangerous carbon monoxide levels) and the alarm didn't resignal, so I kept wondering if it was a fluke or if I should do something about it. Finally, I decided better to play it safe than sorry given that several of my kids had been feeling tired/headaches the past couple days (could've been coincidence) and called the fire department for advice. They came out and sure enough, we had abnormally high levels in the basement. The gas company came out with more sophisticated equipment and pinpointed our furnace--turns out we had a cracked heater exchange that was emitting carbon monoxide. So thankful we had this detector!