Electric leak detectors/shut-offs

[Stephen Tashiro]

What do typical electric leak detector/shut-offs do when the power goes out? - default to turning the water off? - or default to leaving the water turned on?

[Jim Becker]

That's likely relative to the manufacturer and type. The leak detecting valve system that our washer connects to is default to "off" at all times unless the washer is asking for water. When the request is made (washer opens its own valve which the unit in the wall can somehow sense) power is applied to open the valve. The sensor that's down in the pan wouldn't do anything unless water is actually flowing through the valve by request of the washer but if it detects real water, it kills the power to the unit which shuts the valve. If the power is off in the house, no water can flow through that valve since it's default closed with no power. At least that's how the plumber who installed it explained it...