Bests & Worsts Reviews from Amazon

Purchased four of these CO2 alarms and placed them throughout house. We have propane gas kitchen stove, gas fernis, and gas water heater. The water heater is located in the closet of my daughters bedroom (manufactured home). Had alarms for about two months with no issues. Then suddenly one night bout 1:30 am the alarm in my daughters room began going off. Per instructions on back of alarm states 4 beeps = CO2 present. Unplugged alarm and swapped with other alarm in kitchen. About an hour later alarm in daughters room started going off again four beeps. Called fire department responded with CO2 meter. Located high levels of CO2 coming from water heater area in my daughters closet. Ended up the vent under house was plugged up with mouse nest and needed to be cleaned out. Haven't had an issue since. With all that said I thank God I brought these alarms. Wouldn't of had no idea of presence of CO2 and who knows may have never woken up the next morning. If it is going off (4 beeps) trust it!! You never know. I don't normally right a lot of reviews but I definently took the time to right this one it deserves it and may have saved me and my families lives. If you don't have any CO2 alarms in your house and are thinking about getting some, stop thinking about it and buy them now!