Couples’ sleep-temperature incompatibility is a tale as old as time, and my husband, Carter, and I spent years trying to find a compromise. Making me warmer was easier than getting him cooler, so we mostly focused on him. We tried a cheap cooling mattress pad that oddly had the exact opposite effect. And even though innerspring mattresses typically sleep cooler than foam ones, we didn’t notice a difference after switching between the two. Finally, we began sleeping on breathable linen sheets, with Carter sometimes aiming a small fan directly at his head while I entombed myself under several layers, including a 20-pound weighted blanket. This wasn’t ideal for snuggling, but it worked well enough.
That is, until the past year, when Carter’s night sweats shifted into overdrive. Though his doctor couldn’t find anything wrong with him, he would quickly become drenched every time he fell asleep. He would wake up periodically through the night, cranky and uncomfortable, and I had to wash our sheets every morning. So when Wirecutter’s sleep team put out the call for someone to test the ChiliPad (with the Cube Sleep System), I volunteered Carter.
Electric blankets and heated mattress pads have been around for decades, but cooling contraptions like the ChiliPad and BedJet are newer innovations. Wirecutter has been skeptical of their claims in the past, and for this test we weren’t excited about BedJet, in part because it works by shooting cool air under the covers via what looks like an industrial air duct. The ChiliPad, described as a “reversible hydro-powered mattress pad,” at least seemed designed to distribute its temperature settings more evenly, with a system featuring two parts: a machine-washable mattress pad that encases silicone tubing filled with water, and a separate control unit that circulates the water and regulates its temperature. ChiliSleep, the company that sells the ChiliPad and the Cube system, makes another system, the Ooler, which is essentially a ChiliPad with extras, such as an app that allows you to precool the bed. All of these systems are expensive, with the ChiliPad starting at $700 for a single-person mat that covers only half of a queen-size bed.
The ChiliPad lies flat beneath your fitted sheet, and it’s reversible, with a mesh side designed for cooler sleep and a cotton-polyester blend on the other side for those (like me) who prefer a warmer bed. Sleep as you normally would with a blanket, and the pad promises to keep the temperature around your body consistent for the night. A remote control allows you to adjust the temperature—anywhere between 55 and 115 degrees Fahrenheit—from bed. Eyeing those triple digits, I had to force myself to remember that this test was for Carter.
Setup took us less than 15 minutes, with the pad sliding easily over half of our mattress and held in place with two thick elastic bands. The control unit was less obtrusive than I expected from the photos, a few inches shy of 1 cubic foot, with a screen that displays the temperature. You add approximately 12 ounces of water to the control unit, turn it on so the water gets sucked into the tubes, and slowly pour additional water in until the unit is full again (around 24 ounces total). ChiliSleep encourages using distilled water to avoid potential sediment buildup in the tubing over time.
We programmed the Cube to its coldest setting and placed our hands on the ChiliPad to feel it go to work. It began cooling surprisingly fast, reaching 55 degrees within about five minutes. Then we climbed into bed. I buried myself under my normal blankets and watched as a smile spread across Carter’s face. “It feels nice,” he said. My side of the bed stayed warm as the control unit emitted what we both found to be a soothing hum, barely noticeable against the white noise machine we already use. The control-panel lights turned off after a few moments, eliminating any glow.
The next morning, Carter woke up bone-dry and said he’d slept better than he could remember sleeping in ages. Rolling myself across the ChiliPad’s surface, I could distinctly feel the tubes beneath the padding, but he claimed he’d barely noticed them as he was drifting off. That’s when I spied a few dime-sized spots on our sheets, running along a short stretch of the pad’s edge, following one of the tubes. I worried we’d sprung a leak, despite the company’s claims that the tubing is strong enough to withstand animal-claw punctures.
Carter guessed that the issue might be condensation; he pointed out that the tubes were colder than the air in our room, which has some natural humidity. A PR rep from ChiliSleep confirmed his suspicion and said it’s a common experience for many ChiliPad users. After months of waking to a damp human-shaped shadow on Carter’s side of the bed every morning, I wasn’t concerned about a few tiny water blots, and besides, I’d outfitted our mattress with a waterproof cover long ago.
For the next few weeks, Carter continued to sleep soundly and wake in the morning totally dry, rested, and cheerful. He swears that this thing works better than any techniques we’ve tried in the past, but he does complain about the medical-device aesthetic. “Seeing those tubes running up the side of the bed and under the covers makes me feel like we’re old and broken,” he said.
Existential crisis aside, I’m deeming the ChiliPad a success in our home so far, but a few areas give us pause. First, ChiliSleep recommends washing the pad every one to three months and cleaning the machine once a month with its $8 ChiliSleep System Cleaner. Sold separately, this solution is described as a bleach-free “special mix of essential antimicrobial ingredients.” But using it monthly adds up to almost $100 per year, and I imagine we’d be inclined to try a DIY method instead.
It also took five days to get a response from the company’s customer support line after I first noticed the wet spots. Considering the ChiliPad’s price, this is inexcusable (though both the instruction booklet and the website’s troubleshooting section are very clear about the possibility of condensation, and I should have checked there first).
If you or someone in your life has uncontrollable night sweats, start with a medical visit. Your doctor may be able to find and treat the underlying health issue. If not, the ChiliPad could be the way to find some relief. Neurologist Chris Winter, the president of Charlottesville Neurology and Sleep Medicine in Virginia and author of two books on how to get better sleep, isn’t financially compensated by ChiliPad but probably should be for the amount of praise he gives it. “If you like a cold bed, this thing is amazing,” he told me in an email. Winter also said he has recommended the ChiliPad to many professional athletes who sweat a lot, and he doesn’t know of a single one who didn’t like it. And he told me a colleague has found it helpful for menopausal patients.
On the flip side, Winter said that its slight hum can be disturbing for some people—I’ve seen reviews voicing this same complaint from folks who prefer to sleep in a silent room. And, of course, Winter mentioned that the high cost is a big negative. But at least the ChiliPad is cheaper than most “cooling” mattresses. If you want to try one without committing, make sure you carefully follow the specific conditions of its 30-day free sleep trial so you can return the ChiliPad without a hassle.
Despite our success with the ChiliPad, there are two members of our household who want nothing to do with it—our cats. They’ve always loved Carter’s body heat and are baffled by the mysterious cold that now surrounds him. From the very first night we set the system up, they began cuddling with me instead, so I consider the ChiliPad a double win.
It’s Chill Week at Wirecutter! Read more about ways to cool down and get the most out of summer.