Buying Guide · Updated 2026
A whole-home water monitor watches your entire plumbing system for the kind of leak a point sensor can't see — one hidden inside a wall or under a slab. The three main options differ enormously in install difficulty and whether they can actually stop the water.
Attaches with a rubber strap to the outside of your existing water meter and reads its magnetic dial — no tools, no cut pipes, roughly 10 minutes to install. Renter-friendly, since it's fully removable and travels with you.
Both cut into your main supply line and require an electrical outlet nearby. This is a plumbing modification in every US jurisdiction and a licensed plumber is recommended — expect $200–$400 in labor on top of hardware cost.
Flume 2 is a passive monitor — it will alert your phone the moment it detects unusual flow, but it cannot physically shut off the water. If a pipe bursts while you're at work, you still need to get home or call someone to turn off the main. Moen Flo and Phyn Plus include a motorized shutoff valve, so they can close the water automatically the instant abnormal flow is detected — the difference between "you'll know quickly" and "the water stops itself."
Side by side
| System | Install | Auto shutoff | Power outage behavior |
|---|---|---|---|
| Flume 2 | Strap-on, DIY, ~10 min | No | Battery-powered, keeps monitoring |
| Moen Flo | Inline, professional plumber recommended | Yes | Requires wall outlet — optional battery backup adds up to ~3 days |
| Phyn Plus | Inline, professional plumber recommended | Yes | Requires wall outlet, no battery backup |
Our take
You can install this yourself, and take it with you when you move — nothing else on this list can say that. It's sensitive enough to catch a barely-dripping garden hose, but keep in mind it only warns you. It won't shut the water off.
Every night, it runs a pressure health check that catches pinhole leaks behind drywall before they ever become visible damage — and if something's wrong, it can shut the water off on its own. Of the three, it also has the broadest installer network and the best shot at an insurance discount.
Measures pressure changes 240 times a second — sensitive enough to distinguish a toilet flush from an ice maker filling — with no required monthly fee.
FAQ
Only Moen Flo and Phyn Plus — both include a motorized valve. Flume 2 will tell you about a leak, but it has no way to physically stop the flow.
Yes, with Flume 2. No plumbing modification, fully removable when your lease ends. The inline systems aren't a realistic option for a rental.
Yes, all three need a Wi-Fi connection to send alerts. If your meter or main line sits in a deep basement or far corner, a cheap Wi-Fi extender may be necessary.
Whole-home monitors catch main-line and hidden-pipe leaks; they don't replace point sensors at high-risk spots like under sinks. See our point sensor guide for that layer of protection.