Best smart water shutoff valve: the maker pages sort them into in-line units that sense flow and bolt-on actuators that only close a ball valve, and the pipe you have decides first
Maker pages compared: Moen Flo in-line on 3/4 to 1-1/4 in with flow sensing; Frizzlife LP365 in-line, no hub; YoLink bolt-on for ball valves; Flume monitors only.
- Verified
- Updated
- 11 min read
- 12 sources
Shop links on this page are affiliate links: a purchase may earn us a commission at no extra cost to you. Disclosure
OwnerSpec compares published manufacturer specifications, certification listings and sourced technical documents. Unless a page explicitly states otherwise, OwnerSpec has not laboratory-tested or used the products it compares. Editorial policy
Short answer
For a house with a 3/4 to 1-1/4 in main line and a plumber booked, the pick is the Moen Flo Smart Water Monitor and Shutoff. Moen’s shop page lists three bodies (900-001 for 3/4 in, 900-006 for 1 in, 900-002 for 1-1/4 in), an in-line install that removes a section of pipe and daily microleak tests down to one drop per minute; the 900-001 spec sheet prints flow, pressure and temperature readings, 175 psi maximum operating pressure, IAPMO IGC 349, UL 1951, NSF 61/9 and NSF 372. The runner-up for anyone who will not cut pipe is the YoLink Water Shutoff Kit: YoLink’s EVO page lists a bolt-on operator for 1/2 to 2 in ball valves that closes in under 18 seconds, with no flow sensing, so it waits for a floor sensor to get wet. Skip both if the main shutoff is a gate valve, and skip the whole class if you rent: Flume’s clamp-on meter sensor monitors only.
The picks
Has a 1 in main, a plumber and wants flow sensing with printed standards
Moen Flo Smart Water Monitor and Shutoff, 900-006 (1 in)
Moen shop page: in-line on the main cold supply, daily microleak tests to one drop per minute, 2.4 GHz Wi-Fi; Moen 900-001 spec sheet: flow, pressure and temperature readings, 175 psi max, IAPMO IGC 349, UL 1951, NSF 61/9 and NSF 372, one-year warranty
Has a 1-1/4 in main line that the 1 in body will not fit
Moen Flo Smart Water Shutoff, 900-002 (1-1/4 in)
Moen shop page: 900-002 fits 1-1/4 in or smaller; same in-line install, app and Wi-Fi as the 900-006; its own spec sheet was not opened, so the 900-001 standards are not quoted for it
Wants in-line flow sensing without a hub and with a battery backup
Frizzlife LP365 Smart Water Monitor and Automatic Shutoff
Frizzlife product page: fits 3/4 and 1 in pipe, in-line, 110 V with a 6.5 ft cable and a rechargeable backup of 4 to 6 months standby, Wi-Fi through the Smart Life app, ultrasonic flow 0.001 to 18.00 GPM, micro-leak detection to 0.01 GPM, IP67; no UL or NSF listing printed
Has a quarter-turn ball valve and will not cut pipe
YoLink Water Shutoff Kit (Valve Controller, EVO operator, 3 sensors, hub)
YoLink EVO page: bolt-on, recommended ball valve sizes 1/2 to 2 in, 12 VDC, under 18 seconds to open or close, hub with internet required, shows handle position, no flow measurement
Already owns a YoLink hub and has a 1/2 to 1 in ball valve
YoLink Smart Water Valve Controller with manipulator (hub required)
YoLink YS4909 page: ball valves 1/2, 3/4 and 1 in, 4 AA batteries, hub plus internet required, no flow sensing, install rated Difficult by YoLink
Rents, or cannot touch the plumbing, and wants usage and leak alerts only
Flume F2X Smart Home Water Monitor (monitor only, no shutoff)
Flume homepage: clamp-on sensor on the water meter, no pipe cutting and no wiring, Wi-Fi, optional paid Insight tier; the page states no automatic shutoff
If the leak you fear is the washing machine hose, a plain bolt-on actuator with a sensor under the machine does the job; the hose replacement interval page costs less than any valve here and may be the right first purchase.
How was this shortlist built?
Every figure is a manufacturer-published specification read on 2026-10-09 from the document named beside it. Nothing was installed, run or tested by this site, and every listed unit was confirmed in stock the same day.
Units were compared on pipe size, install type, what the device senses, whether it runs a leak test, the subscription as the maker prints it, power and hub or Wi-Fi. A certifier and a standard number appear only where the maker prints both.
Three gaps are stated, not filled. Guardian, Dome and LeakSmart maker pages could not be read, so those units are absent. Phyn Plus appears in the table but its Amazon listings were out of stock, so it is not a pick. Only the Moen 900-001 spec sheet was opened, so its standards are quoted for that model and not stretched to the 900-006 or 900-002.
An in-line valve is cut into the main supply and carries the water. A bolt-on actuator clamps over the handle of the ball valve the house already has and turns it.
How do the units compare on paper?
| Unit | Pipe or valve size | Install | Senses | Leak test | Subscription as printed | Power | Hub / Wi-Fi | Standard printed |
|---|---|---|---|---|---|---|---|---|
| Moen Flo 900-006 (family: 900-001, 900-002) | 3/4, 1 or 1-1/4 in by body | In-line, pipe section removed, after meter, shutoff and PRV | Flow, pressure, temperature | Daily microleak test, manual Health Tests | None required; optional FloProtect bundle | AC outlet, 100-240 V | 2.4 GHz Wi-Fi, no hub | IAPMO IGC 349, UL 1951, NSF 61/9, NSF 372 (900-001 sheet) |
| Phyn Plus 2nd Gen (out of stock) | 1-1/4 in or smaller, 1 in NPSM male ends | In-line, licensed plumber, 1 to 2 hours | Pressure wave analysis | Not printed | “Free Phyn app”; no fee printed | Outlet within 12 ft, holds state on power loss | Wi-Fi at install point | Not printed |
| Frizzlife LP365 | 3/4 or 1 in | In-line, professional install recommended | Ultrasonic flow 0.001 to 18.00 GPM, micro-leak to 0.01 GPM | App-based leak test mentioned, details not printed | Not printed | 110 V, 6.5 ft cable, battery backup 4 to 6 months standby | Wi-Fi via Smart Life, no hub | None printed; IP67 |
| YoLink EVO kit | Ball valve 1/2 to 2 in | Bolt-on over the handle | Handle position only; leak sensors in the kit | None | Not mentioned | 12 VDC adapter | Hub required, internet | Not printed |
| YoLink YS4909 controller | Ball valve 1/2, 3/4, 1 in | Bolt-on with manipulator, rated Difficult | None | None | Not mentioned | 4 AA batteries | Hub required, internet | Not printed |
| YoLink Bulldog valve robot | Ball valve 1/2, 3/4, 1 in | Bolt-on, about 15 minutes | None | None | Not mentioned | 4 AA or 12 VDC | Hub required | Not printed |
| YoLink FlowSmart Control 1-1/2 in | 1-1/2 in in-line meter and valve | In-line | Pulse-counter flow meter | Not printed | Not mentioned | 4 AA or 12 VDC | Hub required | NSF/ANSI/CAN 61 stainless components |
| Flume F2X | Clamps on the water meter | No pipe cutting, no wiring | Meter usage | None | Optional paid Insight tier | Not printed | Wi-Fi | Not printed |
No maker page read this session prints a hydrostatic pressure test for any unit; Moen’s microleak and Health Tests are the only leak-test features described in detail.
Moen Flo Smart Water Monitor and Shutoff: buy it or skip it?
Buy it if the house has a 3/4 to 1-1/4 in main, an outlet near it and a plumber on the way. Moen’s 900-001 spec sheet lists flow, pressure and temperature readings in the app, manual Health Tests, a 175 psi maximum, an install after the meter, the shutoff and any pressure regulating valve, 2.4 GHz Wi-Fi, IAPMO IGC 349, UL 1951, NSF 61/9, NSF 372 and a one-year warranty. The shop page adds daily microleak tests to one drop per minute and no required subscription.
The flaw is the power rule. The spec sheet wants continuous power from an outlet within 6 ft; the shop page says a 10-foot adapter cable is included with 25-foot extensions sold separately. The two Moen documents disagree, so plan on a nearby outlet and read the current sheet before the plumber arrives. The sheet also bars the Flo from any circuit that feeds residential fire sprinklers downstream and asks for a second shutoff upstream.
The 900-002 is the same unit for a 1-1/4 in main. Its spec sheet was not opened, so the standards above are Moen’s statement for the 900-001 only.
Skip it if the main line reads over 80 psi on a gauge: the Flo goes downstream of the PRV, and the 80 psi page explains why that PRV comes first.
Frizzlife LP365: buy it or skip it?
Buy it if you want flow sensing in the pipe without a hub and with a battery behind it. Frizzlife’s product page lists 3/4 and 1 in pipe, an in-line connection on the main supply with professional install recommended, 110 V through a 6.5 ft cable, a rechargeable backup with 4 to 6 months of standby, Wi-Fi through the Smart Life app, ultrasonic flow from 0.001 to 18.00 GPM, micro-leak detection down to 0.01 GPM and an IP67 rating.
The flaw is the certification line: the page prints no UL, NSF or cUPC listing and only a passing mention of app-based leak testing. A phone or SMS alert subscription is mentioned only in a customer review on that page, so it is unverified here and not counted either way.
Skip it if the insurer matters. Neither insurer page read names Frizzlife, while both name Moen.
YoLink bolt-on kits: buy them or skip them?
Buy the Water Shutoff Kit if the main shutoff is a quarter-turn ball valve and nobody is cutting pipe. YoLink’s EVO page lists a bolt-on operator for 1/2, 3/4, 1, 1-1/4, 1-1/2 and 2 in ball valves, 12 VDC at up to 500 mA, under 18 seconds to open or close and a handle position indicator; the kit adds three leak sensors and the hub the EVO needs.
The flaw is in the sensing column: the EVO reports handle position and measures no flow, so a pinhole behind drywall never trips it. It closes when a sensor puck on the floor gets wet, and the pucks go where the leak detector page says: water heater pan, washer, under sinks.
Buy the YS4909 controller with manipulator only if you already own a YoLink hub. YoLink’s page lists 1/2, 3/4 and 1 in ball valves, 4 AA batteries and an installation it rates Difficult because the manipulator needs fine-tuning.
YoLink’s Bulldog valve robot is the easier bolt-on in the same range: its page lists 1/2, 3/4 and 1 in valves, about 15 minutes with a Phillips screwdriver and 4 AA or 12 VDC power. If you want YoLink and flow data, the FlowSmart Control pairs a pulse-counter meter with a motorized valve and prints NSF/ANSI/CAN 61 stainless components, but it is in-line and the opened page is the 1-1/2 in size.
Skip every bolt-on if the main is a gate valve with a round wheel: each YoLink page lists ball valve sizes only.
Flume: buy it or skip it?
Buy it if you rent, or if the main is behind a wall and you want to know where the water goes. Flume’s homepage lists a clamp-on sensor on the water meter, no pipe cutting, no wiring, Wi-Fi and an optional paid Insight tier.
The flaw is the title of this page: Flume’s homepage states nothing about shutting off water. It alerts; a person closes the valve. The F2X product page returned 404 this session, so the claims above rest on the homepage, which describes the Flume 2 and does not name the F2X.
Skip it if the meter sits in a pit at the street in a cold climate and the Wi-Fi cannot reach it: nothing on the homepage addresses that case.
Look at the main shutoff before you buy
Do not order any unit until two things are known: the pipe size at the main (3/4, 1 or 1-1/4 in decides which Moen body or whether Frizzlife fits) and whether the shutoff is a quarter-turn ball valve or a gate valve (only a ball valve takes a YoLink actuator). A gate valve means the in-line class or a plumber swapping the valve first. If the gauge reads over 80 psi, the PRV comes before any of this.
Will insurance pay for it?
Rarely in full. Mercury’s leak detection FAQ prints an average discount of up to 4.6% of the annual homeowners premium for qualifying devices, with an average saving of about $100 for a device with automatic shutoff and about $75 for a Flume-type monitor, and says automatic shutoff is mandatory only for secondary or seasonal homes with Coverage A of $2 million or more.
Amica’s discount page lists all-in-one flow, pressure and temperature devices with automatic shutoff as a qualifying type and names Phyn, StreamLabs, Flume and Moen as partner brands. It prints no percentage and says availability varies by state. No insurer page read names YoLink or Frizzlife.
The reason to buy is the burst you are not home for. A failed heater tank is one way it happens; the water heater leaking page shows where it starts, and a Flo or an actuator with a puck in the pan closes the main while you are away.
What goes wrong?
The valve is not powered. Every in-line unit on this table needs an outlet near the main. Phyn’s page says its valve holds whatever state it was in when power is lost; Frizzlife prints a battery backup; Moen’s sheet asks for continuous power.
A frozen pipe bursts upstream of the valve. A shutoff after the meter does nothing for the meter pit or the service line. The frozen pipes page covers insulation and heat cable, which is the only fix for that run.
The actuator slips. YoLink rates the YS4909 manipulator install Difficult and the EVO and Bulldog bolt on instead; a bolt-on that cannot turn a stiff valve is a sensor with no hands. Work the ball valve by hand first. If it will not move, that is the plumber visit, and the sump pump page is the other half of the basement plan while the plumber is there.
Frequently asked questions
Does a smart water shutoff valve need a plumber?
The in-line units do. Moen's page says the Flo is installed on the main cold supply, which requires removing a section of pipe, and Phyn recommends a licensed plumber for 1 to 2 hours. The bolt-on actuators do not: YoLink's Bulldog page says no pipe cutting and about 15 minutes with a Phillips screwdriver, on a quarter-turn ball valve of 1/2 to 1 in.
What is the difference between a flow-sensing valve and a valve actuator?
A flow-sensing valve such as the Moen Flo sits in the pipe and reads flow, pressure and temperature, so it can close on a leak nothing else has noticed. An actuator such as the YoLink EVO only turns the handle of the ball valve you already have, and closes when a separate leak sensor gets wet. It cannot see a slow leak inside a wall.
Does the Moen Flo require a subscription?
Moen's shop page prints no required subscription for the valve's core function. It sells an optional bundle with a three-year FloProtect plan that adds an extended warranty and up to $5,000 in insurance deductible coverage. The 900-001 spec sheet lists flow, pressure and temperature readings and manual leak tests without naming a plan, so this page treats the plan as optional.
Will a smart shutoff valve lower my home insurance?
Sometimes, and by less than the valve costs. Mercury's FAQ prints an average discount of up to 4.6% of the annual homeowners premium for qualifying devices, and says automatic shutoff is mandatory only for secondary or seasonal homes with Coverage A of $2 million or more. Amica names Phyn, StreamLabs, Flume and Moen as partner brands but prints no percentage and says availability varies by state.
Does Flume shut off the water?
No. Flume's homepage describes a clamp-on sensor on the water meter, no pipe cutting, no wiring and Wi-Fi, and states nothing about closing a valve. It alerts to usage and leaks and is the only device on this page a renter can fit, but when it reports a burst hose someone still has to walk to the main and turn the handle.
Fact sheet and how to cite this page
- Answer
- For a 3/4 to 1-1/4 in main line and a plumber, the pick is the Moen Flo Smart Water Monitor and Shutoff: Moen’s 900-001 spec sheet prints flow, pressure and temperature sensing, 175 psi maximum, IAPMO IGC 349, UL 1951, NSF 61/9 and NSF 372. For an existing ball valve with no pipe cut, the YoLink EVO kit bolts onto 1/2 to 2 in valves and closes in under 18 seconds, but senses no flow.
- Comparison basis
- Maker product pages and spec sheets for the Moen Flo (900-001 spec sheet and shop page), Phyn Plus 2nd Gen, Frizzlife LP365, YoLink YS4909, EVO, Bulldog, DN25 and FlowSmart pages and the Flume homepage, compared on pipe size, in-line versus bolt-on install, flow sensing versus sensors only, leak test feature, subscription as printed, power and hub or Wi-Fi, plus two insurer discount pages.
- Assumptions
- The main shutoff is a quarter-turn ball valve; a gate valve takes none of the bolt-on actuators
- The Moen 900-006 and 900-002 share the 900-001 design, but only the 900-001 spec sheet was opened, so its standards are quoted for that model only
- An outlet exists near the main; every in-line unit on this page needs one
- Method
- OwnerSpec compared manufacturer-published specifications read on 2026-10-09 and confirmed each listed unit in stock the same day; it did not install, run or test any valve, and prints only the figures the cited document states. Guardian, Dome and LeakSmart pages could not be read, so those units are absent.
- Primary source
- Moen, Flo 900-001 specification sheet (PDF) (manufacturer or vendor document)
- Facts verified
- Last updated
- Cite as
- OwnerSpec, "Best smart water shutoff valve: the maker pages sort them into in-line units that sense flow and bolt-on actuators that only close a ball valve, and the pipe you have decides first", https://ownerspec.com/plumbing/reviews/best-smart-water-shutoff-valve/, facts verified 9 October 2026.
Every figure above also appears, with its source, in the article. All sources ยท How OwnerSpec verifies numbers
Sources
- Moen, Flo 900-001 specification sheet (PDF) (manufacturer or vendor document)
- Moen, Flo Smart Water Monitor and Shutoff (shop page) (manufacturer or vendor document)
- Phyn, Plus Smart Water Assistant + Shutoff (2nd Gen) (manufacturer or vendor document)
- Frizzlife, LP365 product page (manufacturer or vendor document)
- YoLink, EVO Valve Operator (manufacturer or vendor document)
- YoLink, Water Valve Controller (YS4909) (manufacturer or vendor document)
- YoLink, Valve Controller 2 with Bulldog Valve Robot (manufacturer or vendor document)
- YoLink, Valve Controller 2 with DN25 brass motorized valve (manufacturer or vendor document)
- YoLink, FlowSmart Control 1-1/2 in meter and motorized valve (manufacturer or vendor document)
- Flume, homepage (manufacturer or vendor document)
- Mercury Insurance, Water Leak Detection Services FAQ (manufacturer or vendor document)
- Amica, Water damage mitigation device discounts (manufacturer or vendor document)