Water is GREAT Stuff right? Not so much when it’s forced to leave it’s designated home and starts swimming around your home’s floor space instead. I know this is an ‘after-the-fact’ project, but I hope it can help someone else avoid a potential flood and damage. Our hot water heater’s expansion tank blew a pinhole leak recently and started spraying water with a fury. Thankfully the closet door it sets behind contained it’s aqueous projectile path which minimized the damage. That…and the fact that I actually heard the HISSING noise saved us…THIS TIME. If I had installed the Gizmo you’ll see here, I would have heard it a LOT sooner. The kicker is, I set something similar to this up last year just ‘geeking’ around with some of my toys. Hindsight Mannn! This particular Instructable is for a basic leak detector that only notifies with an audible alarm and visual LED.”

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