This unit works effectively after it has been going for a few weeks. Unfortunately, the quality control is terrible. Within 2 weeks to 6 weeks the unit won't restart and I get a double flashing red light indicating a thermostat problem. The manufacturer will gladly take the unit back and repair under warrant, but this involves packing and shipping it and not having its use during mosquito season. Rather than do that, fortunately, Home Depot's return policy is extremely generous and I have returned two units so far and the current one is now not working. I am about ready to give up on this product. Its a shame that the manufacturer just doesn't get it!