FIRST ALERT Combination Explosive Gas and Carbon Monoxide Alarm with Backlit Digital Display, GCO1CN

I picked this detector because it covered all the bases for various gasses and has an outboard power supply. This let me mount it in an ideal location then pass the wire through the wall to an outlet in a closet for a clean install. I can't speak to actual functionality since I hope it never goes off, but I've had no false alarms.

This is a really loud alarm. All you need to do is putting in batteries and plugging into the outlet. It doesn’t need to change battery for really long time. This is a great reliable detector for my basement. There is instructions printed on the device, so you don’t have to look up what to while it beeps loudly to your ears.

Bought one of these 9 years ago. About a month ago I woke one morning and this thing was going off. The display said "Gas". I went to every room in the house including the attic and smelled nothing. I kept resetting the detector moving it from room to room and it kept going off. Called the fire department. They checked my house and attic and found nothing. They told me it was 9 years old and may be defective. But since I called them, they had to call the gas company. They came out and had a real sensitive sniffing machine. Found nothing in the house. But in the attic found a tiny leak on a pipe union that you could not smell standing right there. This detector did its job! A few days ago it starting giving 3 short beeps every minute. That means it needs to be serviced. Well, I decided to throw it away and buy a new one. No telling how long we could have lived in our house with gas fumes if we had not owned this detector.

The packaging states that a 9 V battery is included. The packaging (clear plastic bubble) was cut open just slightly where the battery would’ve been and the battery was missing. Otherwise, the product works as intended. I use this in conjunction with another device for comparison. So at this time, my only issue was that the product was received without the included battery.

Good tester, but verify the Expiration Date upon receipt. Some sellers provide NOS testers that are near their end, even though apparently new.

I've had this Brand for years. Tested them and they work great.

Honestly, Do any of these alarms work? Unfortunately, the only way to really find out is if you have a gas leak or carbon monoxide present. if it works it's great and you'll be singing it's praises but if it fails, hopefully, you will not suffer injury and will be around to let others know of it's failure. This one failed it's first test. It failed to alarm during a gas leak.I purchased this alarm in December 2016 after having a new vent-less space heater installed in my living room/den. One of the gas line connections leaked and wasn't discovered until the next day. I began shopping then for a carbon monoxide detector with a gas leak detector.I decided on this model and purchased and installed it according to the enclosed recommendations.Less than one month later I came home from work and the entire house smelled of propane, every single room. I called a technician who found a leak inside the heater. The propane smell was strong and very noticeable after leaking into a closed home all day, however the First Alert Alarm didn't detect the leak.The detector was installed, as per instructions and in the same room as the heater and it didn't alarm-not once. It's been installed less than 60 days and it doesn't work. I tested the alarm at installation and every week as indicated but it failed to alarm when needed. I even took the alarm down and placed it near the heater where I was smelling the propane the strongest, while waiting for the technician, and it still failed to alarm.I now wonder if it ever worked or would have worked if it had been carbon monoxide instead of a gas leak. It certainly gave me a false sense of security.

These detectors seem to work well. I've just never had a problem with this model unit. Previous units of this type have alerted when gas (propane in my case) was present. Can't attest to CO2, but I feel they likely will detect other gases as the manufacturer states. They've simply been detectors I've relied on and have never had a problem with First Alert GC series detectors. I have them in several locations and again, depend on these units...