Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Had two of these - both failed

I have owned two of these devices. I got rid of each of them because of false alarms with the gas detector. I tried unplugging it and waiting, but the gas alarm continued to sound. I tried vacuuming the unit, but still no help. I'm going with a CO-only detector this time. I have used the Nighthawk CO-only detector in the past and was happy with it. I wish that I had not switched to the CO/gas detector.