This tool literally saved me thousands of dollars and incalculable emotional stress. Watercop attaches to the water main on your house and is triggered by remote RF water sensors that can be placed anywhere. When triggered, it shuts off the main and stops all water flowing into the house.
I installed the Watercop 5 years ago with remote sensors in 4 locations and it sat silently, doing absolutely nothing for all that time. A few weeks ago we got back from a week long vacation and immediately discovered that there was no water coming through our faucets. My first thought was that the Watercop had experienced a power fault and failed closed.
I went down to the basement and, in fact, the Watercop was closed. I turned it back on and heard a gusher from our furnace room. You can imagine my shock when I ran into the furnace room and discovered that the floor of our 15-year-old hot water heater had burst and the Watercop sensor in the room was submerged.
I don’t even want to contemplate what would have happened during that week if there had been no automatic shutoff on the main. The damage to our house and personal possessions, along with the inevitable mold, would have been a disaster.
Not only did it work flawlessly, but you can qualify for an insurance discount if you you have it installed by a licensed plumber (you can install it yourself, but it does require decent plumbing skills). As far as setup, you can place the sensors anywhere. The only downsides I have found is that it is not cheap, you have to replace the batteries annually, and it runs on A/C power meaning that when the power fails so does the device.
Despite these few drawbacks, I can not recommend the WaterCop highly enough. This is, without a doubt, the most valuable tool I have ever purchased.