X-Sense SC07 10-Year Battery Combination Smoke & Carbon Monoxide Alarm Detector

Sounds like there is something wrong with it and you need to contact the manufacturer's customer support (battery is dead?). Mine does not do that. Just occasionally blinks a green light. If the light blinks yellow, it indicates a fault. There is a test/silence button on the unit's face.

It does work, when there is something burning on the stove or it detects carbon monoxide. I had two situations already where this device actually did what it was meant to do is give alert. It is really loud. The colors indicate if it's safe again.

No, to ensure proper functioning, it is recommended to mount this alarm on any wall or ceiling with our included mounting bracket, screws, and anchor plugs.

Yes, there is a green flashing light when it is activated. You can also monitor the battery life through the display as well.

No. You activate the lcd light by pushing the button. Otherwise it's off.