Review: Thermacell LIV Smart Mosquito Repellent System 2.0

Four years ago, I moved back to Texas from California. After two weeks of living here, I realized we were going to have to do something about the mosquitoes. In the 25 years I’d been gone, they seemed to have grown larger, more intelligent, and much thirstier. My skin had become a bepoxed nightmare within days.

I immediately embarked on a mission to do something, anything, about the problem, quickly resorting to paying a local company to send a guy with a pesticide-blasting cannon strapped to his back to the house once every three weeks. The cannon, used to blast all the foliage on the property, was expensive—four figures yearly—and very effective at warding off bugs … for a mere 48 to 72 hours after each spraying, after which it would wear off and the mosquitoes would return with bloodthirsty vengeance.

It took two years for me to find something better, and I wrote about it extensively for WIRED. Thermacell is a leader in mosquito abatement, and its LIV Smart Mosquito Repellent System is the company’s top-tier product. While it produces various small-scale repellers designed for personal use, LIV is a different animal that is installed semi-permanently around the area you want to protect. You fire it up when you need it, then shut it down when you’re safely inside.

Now two years after that review, Thermacell has upgraded most of the LIV components (only the cabling remains the same) and dubbed the system LIV 2.0. The company recently provided me with all the new hardware so I could test whether and how the technology had improved.

Similar Story, Updated Look

Conceptually, you won’t find any big twists in LIV 2.0. The brains of the system include one or more Wi-Fi-connected control hubs. These plug into wall power and connect via lengths of cable to multiple pesticide-emitting repellers laid out in a daisy chain, which you arrange in a perimeter around the area you’re trying to protect (in my case, the swimming pool). Repellers can be placed up to 20 feet apart from each other, and each contains a replaceable vial of the chemical metofluthrin, which mosquitoes detest (though, take note, it doesn’t typically kill them). With the original LIV, I used two hubs and five repellers to ring my pool. This year I added a sixth repeller to enhance coverage in one corner where I worried mosquitoes were sneaking through a hole in the vaporous fence.

Photograph: Christopher Null

The v2 hubs look very much like the original ones, with a circular design that features only a single button on the front that can be used to power the unit on or off (handy in case Wi-Fi isn’t cooperating). A hub can now handle up to 10 repellers (up from 6) and now features two cable terminal posts, so repellers can branch out from the hub in two directions instead of just one. In other words, you no longer have to locate the hub at the beginning of a run, which can add some much-needed flexibility depending on where your power outlet is located. The only other major change of note is that the mounting bracket has been slightly redesigned, so you’ll need to drill at least one new screw into your wall if you are replacing the old system with the new one.

The new repeller design is more exciting to talk about. While it maintains the overall cylindrical design of v1, the styling and operation have been updated. First, the LED status ring that indicates whether the unit is on (or warming up or cooling down) is much easier to see, so you can easily tell at a glance if the system is running, making it less likely to accidentally leave it running for hours when you don’t need it. The bigger news, however, relates to a new hatch on top of the repeller that flips open when it’s warmed up and operational. This new design allows the metofluthrin vapor to rise upward from the repeller instead of simply seeping out laterally, potentially improving airborne coverage of the chemical.

The chemical repellent hasn’t changed—it’s still 5.5 percent metofluthrin—but Thermacell is now marketing it as effective against not just mosquitoes but also midges/no-see-ums, thanks to updated EPA guidance. Midges are the one plague we seem to avoid in my area, so I haven’t been able to test those claims specifically. Also, as I mentioned in the previous review: Make sure you wear gloves when handling the metofluthrin capsules, as it can create a lasting numbness upon contact with skin.

Finally, there’s a new app to run all of this, and it’s a significant improvement over the original LIV mobile app. A scheduling system and timer are handy, and you can even use the app to change the color of the LEDs on the LIV repellers. The app can be a little finicky—it tends to take a few seconds for power state changes to be reflected—but in months of testing this summer, I’ve found that it works well most of the time. What’s missing? Despite promised Alexa support—which vanished abruptly over a year ago—the company says it is still in the works.

ScreenshotScreenshot: Christopher Null

ScreenshotScreenshot: Christopher Null

ScreenshotScreenshot: Christopher Null

Baby Steps

Ultimately, I think the overall effectiveness of the system has improved, though only slightly. A big part of that is that the new top-mounted repeller hatch helps the system warm up faster, not just creating a more effective barrier but doing it more quickly than the older system. With LIV 1.0 I often waited a half hour to see a significant drop in insect activity. With the new system, it seems safe to venture out within about 15 minutes. That said, tenacious bugs desperate for my delicious A-positive blood do still make it through the vapor shield from time to time. Perhaps they are just that hungry.

Another wrinkle is that pricing has unfortunately gone up—now starting at $1,746 for one hub and three repellers—and perhaps more important, it’s no longer available as a DIY solution. Thermacell’s website now refers you to “find a pro” for installation, and in fact sent a professional crew to upgrade my repellers instead of having me do it myself, despite the simplicity of the job. Refill pricing, at $250 for a six-pack of 100-hour cartridges, remains unchanged (and still very pricey).

All told, LIV 2.0 offers some advantages over the older system, but they’re incremental, and if you have a working LIV system already, there’s no overly compelling need to upgrade to this one. If, however, you are looking for a new and effective mosquito barrier system for your pool or yard, LIV is a highly worthwhile option that works better than almost anything I’ve tested to date. It ain’t cheap, but neither is treatment for encephalitis.

Power up with unlimited access to WIRED. Get best-in-class reporting and exclusive subscriber content that’s too important to ignore. Subscribe Today.