I have in December 2012 four of these highly visual smoke detectors Merten buy order in my apartment to take care of a little more security. As I said, from the outside makes the "Merten 547119 ARGUS smoke detector Basic" quite what ago, but the technology seems consistently to have a quirk. Of the four smoke detectors I have attached me to the ceiling, dissolved within the past eight months three for no apparent reason alarm. Two of them even several times. When the first detector in the living room, within one month, middle of the night, two false alarms spent, I even thought of a "Monday Model"; However, the other moved to very soon. A battery change (was an attempt by me to the spook to put an end despite LongLife batteries) managed no remedy and according to the tester button and the indicator light work, the smoke detectors properly. I can not explain why it has come to this false alarms me anyway. But in my opinion, only a technical deficiency is in question, because another smoke detector Gira fully functional hanging for quite some time on the ceiling without making a peep. Today I have removed all four smoke detectors. Since I am professionally sometimes go and have to work at night now and again, it has been apparently pure luck that so far not a false alarm was triggered while I was not there. Pity about the beautiful detectors and almost 120 the total now gone up in smoke.
