Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Flood detector doesn't work at all.

I bought six of these detectors since I have a Visonic wireless alarm system. I have installed many other Visonic devices and all them work perfectly. I'm talking about PIR detectors, fire detectors and door/windows detectors. I was very happy with the overall performance of my system until I bough these flood detectors. Flood detector is supposed to work when water makes a "bridge" between the inside and outside metallic part at the end of detector. The best way that I could find that system was working in theory is with a small electric cable, if you make a bridge with the electric cable between the inside and outside parts the red led works perfectly and signal is transmitted, but it never works when you try to make this bridge with water. I feel that I lost 250 $ because as I said I bought six of these detectors and none of them work in any way with water.