Mosquitoes don't stand a chance against the Thermacell EL55 Mosquito Repeller

CNN

2 days ago

The Thermacell EL55 Mosquito Repeller is a mosquito-hater's dream. Even though mosquitoes aren't as big of a problem where I live in Colorado, camping in the spring still means I get eaten alive by swarms of the bloodsucking creatures, and I can't stand it.
I wear the best bug sprays while I'm hiking to keep me protected, but I don't like stinking up my entire campsite with DEET when I don't have to. That's why I'm in love with the Thermacell EL55. It's a small device that creates a mosquito-free bubble so you don't have to worry about bites.
Thermacell EL55 Rechargeable Mosquito Repeller and Glow Light
Thermacell's mosquito repellents work great, but this iteration might be the best version yet, thanks to its integrated light. If you're always getting eaten up by mosquitoes at your campsite, this repellent is for you. First things first, the Thermacell actually works. I've tested it on several camping trips, and it does a great job at keeping mosquitoes at bay. However, it is important to note that the Thermacell only repels mosquitoes, not all bugs. So, if you have issues with biting flies or getting bombarded by annoying gnats, you'll have to use regular bug spray.
But if mosquitoes are your issue, the Thermacell works well. I've set it up while camping and just hanging out at the park on multiple occasions, and whenever I use it, I don't notice any mosquitoes hanging around, and I was able to escape my outing bite-free. Plus, the Thermacell barely makes any noise, and the repellent it uses doesn't smell.
The Thermacell EL55 works by heating a cartridge filled with a mosquito repellent. Once heated, the device gently sprays the repellent into the air, creating a cloud with a 1-foot radius, according to Thermacell. The active ingredient in the repellent is metofluthrin, not DEET. But don't worry, it's been proven safe for use around both humans and dogs.
'According to the US Environmental Protection Agency (EPA), metofluthrin exhibits low acute toxicity to mammals when used as directed and is classified as 'practically nontoxic' by oral, dermal and inhalation routes. However, cats are uniquely sensitive to pyrethroids, including metofluthrin,' Karthikeyan Chandrasegaran, an assistant professor of entomology at the University of California, Riverside, said. 'Metofluthrin is generally safe for dogs and other mammals in well-ventilated outdoor settings, but cat owners should exercise caution and avoid indoor or confined use where vapors may accumulate.'
Beyond its safety and efficacy, I also love how easy it is to use. Wherever you are, all you have to do is find a flat surface to rest it on, then press the center button. Lights around the button will flash as the device warms up, then turn solid once the device starts releasing repellent. The instruction manual states that the 20-foot mosquito-free zone can take up to 15 minutes to fully establish. The lights on the device also indicate battery life and charging status.
Speaking of battery life, the EL55 can release repellent for a whopping nine hours, according to Thermacell. When I tested the device's battery life for this product review, it did in fact last right around the advertised nine hours. However, that big number is with the light off. With the light on and the repeller active, the battery life drops to around five and a half hours, which was reflected in my testing.
Repelling mosquitoes is a benefit you can find in the normal Thermacell E55, so why spend the extra $20 and get the one with the light? I like to make my camping checklist as efficient as possible, which means products that perform double or triple duty are a big plus. The lantern built into the EL55 is quite good and can illuminate a picnic table at a campsite or the inside of a tent. It doesn't have all the features of the best camping lanterns, such as additional colors or modes and a hook to hang it, but it's still a solid light. Plus, you can use the features of the EL55 separately or together, which makes it quite versatile.
I would definitely recommend the Thermacell EL55 to campers and anyone who hates being outside with mosquitoes in the summer, but even though I love it, there are some imperfections.
My biggest issue is with its portability. It's small — about the size of a softball — which means it's easy to throw into any bag, but there isn't a way to lock the device so it doesn't accidentally turn on.
One time I went on a camping trip and threw a Thermacell E55 into my camp box. When I showed up to camp and opened the box, the entire (new) repellent cartridge was drained, the battery was dead and my gear was covered in repellent. The repellent capsules come with caps, so you could either put the cap on the cartridge or remove it from the device altogether to avoid contaminating your gear.
However, the Thermacell could still accidentally turn on and drain its battery if not stored carefully. This is especially true with the EL55, since there's a button to turn on the repeller and a separate one to turn on the light. A locking feature is found on most camping lanterns and headlamps to avoid this exact problem, and it's something I'd love to see on Thermacell's next repellents. Even without this feature, you can take the top off the EL55, which prevents the device from turning on, to prevent any drained batteries.
Besides accidentally turning on, the only other thing I don't like about the Thermacell EL55 is its price. Not for the device itself — I think it's well worth $50 — but rather the repellent.
The EL55 comes with one 12-hour cartridge, but replacements cost $20 for 36 more hours or $55 for a three-pack that should last you 120 hours. The longevity of these refills depends on how often you use them, and if you're only turning on your Thermacell for an hour or two a handful of times a month during the summer, the refills might last years. But if you're bringing the EL55 camping and using it for four or five hours every night, you might be buying refills more than you'd like.
Cutter, the brand that makes one of our favorite bug sprays, makes a similar device that also uses metofluthrin as an active ingredient. Because of that, it should have similar efficacy, but I haven't tested it yet. Another alternative people use is citronella candles; however, when we talked to entomologists while researching for our guide on the best bug repellents, they only recommended products with ingredients proven safe and effective by the Centers for Disease Control and Prevention (CDC) and EPA, such as DEET and picaridin.
Of course, wearing bug spray is always an option, but I love how the Thermacell provides protection without making my skin and clothes sticky. Thermacell also has different variations of mosquito repellents, including the original E55, the more rugged EX55, the E65 with a fast-charging base and a few fuel-powered options.
If mosquitoes see you as a free and unlimited blood buffet every evening but you hate bug spray, the Thermacell EL55 is the perfect product for you. It's easy to use, effective and versatile thanks to its built-in light. Refills are expensive, and you should pack the device carefully while traveling, but it's the perfect way to avoid mosquitoes, whether you're hanging out in your backyard or the middle of the woods.
The following FAQs have been answered by Kai Burkhardt, writer of this guide and CNN Underscored's outdoors editor; Adam Goess, the executive director of product development at Thermacell; and Karthikeyan Chandrasegaran, an assistant professor of entomology at the University of California, Riverside.
Are Thermacell's repellents effective?
Are Thermacell's repellents effective?
Yes, Thermacell's mosquito repellents are quite effective. The active ingredient, metofluthrin, has been proven effective at repelling mosquitoes, and when I've set up my Thermacell at camp, mosquitoes have left me alone.
How does Thermacell work?
How does Thermacell work?
The Thermacell mosquito repellents work by heating a cartridge of repellent, then spraying that repellent into the air to create a bubble that mosquitoes stay away from.
Are Thermacell's products safe?
Are Thermacell's products safe?
The active ingredient in Thermacell mosquito repellents, metofluthrin, is classified as 'practically nontoxic' by the EPA. 'However, cats are uniquely sensitive to pyrethroids, including metofluthrin,' Chandrasegaran said. 'Metofluthrin is generally safe for dogs and other mammals in well-ventilated outdoor settings, but cat owners should exercise caution and avoid indoor or confined use where vapors may accumulate.'
Does a Thermacell repel flies?
Does a Thermacell repel flies?
'Thermacell's rechargeable line does not work against flies or gnats; however, our fuel-powered line does offer multi-insect repellent refills for black flies and no-see-ums, in addition to mosquitoes,' Goess said.
Chandrasegaran echoed the same. 'Thermacell devices are highly effective against mosquitoes, but their performance against houseflies is limited,' he said. 'Metofluthrin works by releasing a vapor that disrupts the sensory cues mosquitoes use to find humans. However, houseflies rely more heavily on visual cues and decaying organic matter rather than scent-based host detection. As such, they are less susceptible to spatial repellents like metofluthrin.'
Does a Thermacell work on gnats?
Does a Thermacell work on gnats?
'Biting gnats, such as no-see-ums, are blood-feeding insects that rely on olfactory cues similar to those used by mosquitoes,' Chandrasegaran said. 'Thermacell repellers, which release metofluthrin vapor, may offer moderate protection in these cases. While direct studies on metofluthrin and biting midges are limited, research on transfluthrin — a structurally similar compound — has shown promising results.'
'Thermacell may provide relief from biting gnats, but it is not effective against nonbiting gnats,' Chandrasegaran added. 'For the latter, targeted environmental and biological control strategies are more appropriate.'
How long does a Thermacell last?
How long does a Thermacell last?
According to the brand, the Thermacell EL55 can last up to nine hours if you're only using the repeller and don't turn on the light. The cheaper E55 can last up to five and a half hours, according to Thermacell.
For this article, we consulted the following experts to gain their professional insights.
Karthikeyan Chandrasegaran, assistant professor in the entomology department at the University of California, Riverside
Adam Goess, executive director of product development at Thermacell
CNN Underscored editors thoroughly test most of the products we cover and provide full transparency about how we test them. We have an experienced team of writers and editors with many years of testing experience who ensure each article is carefully edited and products are properly vetted. We talk to top experts when it makes sense to ensure we are testing each product accurately and speaking about the pros and cons of each item.
For this article, outdoors, sustainable living and pets editor Kai Burkhardt spoke to an entomologist and the team at Thermacell to get the lowdown on the device's active ingredient. He also spent time extensively testing the repeller himself while camping and hanging out in parks to give his honest opinion.