WaterCop

Moore Family
of Arizona

Water-Cop Water Leak Alert System

The Ultimate Whole House Water Leak Protection System:

After a flood in the kitchen caused thousands of dollars of damage we installed a flood alarm and auto water shutoff system called Water-Cop.

The installation preparations were extensive including a new supply loop, a pressure reducing valve, new shutoff valve & water hammer arrestor, the Water-Cop isolation valve, a whole house sediment filter a water softener and an expansion tank. The monitoring side includes water sensors located at every water outlet inside the house: for a total of 18 sensors. I used hardwired sensors wherever possible connected back to a monitoring station & remote shut/off controller in the utility room. Only for the kitchen island and the far west-side of the master bedroom I did use wireless sensors due to difficulty wiring to those locations. In each case these are equipped with a permanent 110v power supply.

For some of the hardwired sensors I needed to create custom sensors to add double and triple sensors to some channels (for adjacent areas). WaterCop is a resistance sensing system and can detect open and short circuit sensors as well as wet conditions. I adapted some 3rd party sensors from eBay (by adding 500K Ohm effective total sensor channel resistance). So 1 M Ohm per sensor for 2 sensors and 1.5 M Ohm per sensor for 3 sensors - this works well. The sensing and auto water shutoff works well and seems to be a well engineered system.

However I foresee a continuing problem. The water shut-off valve requires that an expansion tank be fitted on the house side of the tank (for hot tank pressuraization). So even when the valve shuts off pressure remains due to the residual water pressure in the supply lines and also the expansion tank. These can cause a still significant amount of water to leak even when the main supply is fully turned off. So a risk of some flooding remains due to the combined expansion tank/line pressure & volumes (approx 1.5 gallons) and the RO tank volume of approx 1.5 gallons.

Testing reveals that with the expansion tank off the line pressure allows 1.5 quarts of water to be expelled before the system pressure reduces close to 0 PSI. With the expansion tank on there is close to 1.5 gallons of water expelled before the system pressure reduces close to 0 PSI. More water than this can leak due to line elevations - but once the pressure is reduced the flow will also be reduced, likely to 0 for most small leaks.

To address this remaining issue I have come up with a provision for isolating or draining the storage/pressure tanks still connected to the system. The Water-Cop Pro monitoring station provides a low voltage relay output suitable to connect to a home security system (for alerts) that can be adapted for this purpose. So I have designed a drain-off system for the primary expansion tank - whenever the Water-Cop alerts for a water leak, the main shut-off valve closes and concurrently a one way drain valve relives pressure from the expansion tank to the water softener drain - this will take a minute or so to fully drain down all the water pressure. At the same time a remote control X-10 shutoff valve isolates the RO storage tank in the kitchen sink island cabinet (in case that was the source of the water leak). These backup systems are only activated in the case of a water leak being detected - the valve can be turned off manually while maintaining system pressure as long as there is no active water leak alarm.

I consider that with this additional modification my Water-Cop installation is truly the ultimate in water leak protection.