· Burnt Food on the Stove top. If you don't supervise the stove when cooking, your dinner may produce smoke, which activates the smoke alarm. … · Cigarette smoke directed toward the smoke detector (but usually not ambient cigarette smoke). · Thick steam within a closed room or Kitchen. · Chemical Smells. · An Old or Faulty Smoke Alarm · A common cause of false fire alarm is the unintended triggering of a manual call point, mostly put in insecure areas where it is easy to knock or strike delicate 'break glass' units which will activate an unwanted fire alarm.