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An honest review of the ChiliSleep OOLER Sleep System

Can a mattress pad provide luxurious — and cool — sleep?

That’s what ChiliSleep claims its new OOLER Sleep System can deliver. The hydro-powered thermal pad is designed to keep you cool at night by circulating water through a pad placed between your mattress and fitted sheet with the goal of keeping hot sleepers cool, and cold sleepers warm. A control unit sends the water back and forth between it and the pad, sending it out at a temperature you specify (55-100 degrees Fahrenheit). The unit can be operated manually or through a Bluetooth phone app.

Through all this, ChiliSleep guarantees a long, restful night’s sleep and a comfortable bed to boot. I set out to see if the OOLER system was really an all-around winner.


  • Easy to unbox and set up
  • Bluetooth controllable
  • Wide temperature range
  • 30-night trial period
  • Two-year warranty


  • Design not optimized for all bed and bedroom styles
  • Warm Awake feature not always reliable
  • Sound it emits can be bothersome

Unboxing and setup

The OOLER Sleep System arrived in a box perfectly designed to securely fit the control unit — an oval-shaped water reservoir with flat white buttons — and all the necessary coiled cables and wires. The half queen-sized mattress topper fit perfectly on my mattress, though the attached fabric loops meant to help keep it in place weren’t the perfect size to fit snugly around my mattress. Once I put my fitted sheet back on the bed, I couldn’t even tell the OOLER pad was there. The hoses connected to the OOLER system are a bit too bulky to hide but are easily long enough to allow you to conceal them and the water tank almost anywhere.

The OOLER system’s patented cooling and warming water technology requires about 32 oz. of distilled water to work its magic. After pouring the water in the tank and pairing the OOLER system with the iOS app, it was ready to go.

While the OOLER’s tank isn’t large, the space requirements can be limiting. It requires about 6 inches around it on all sides to allow for proper venting. I own a platform bed without under-bed storage, so there was nowhere to put the unit and the hoses except beside the bed, which wasn’t the most ideal storage solution.


Initial impressions of the ChiliSleep OOLER Sleep System

It was incredibly refreshing to lie down in bed and not immediately break into a sweat. Using the app, which connected to my OOLER system via Bluetooth, I was able to pre-cool the bed so it was at the perfect temperature for me. I also rejoiced in knowing the OOLER system has a temperature range from 55 to 100 degrees Fahrenheit — if by some miracle, I ever got too cold while sleeping, I now had a way to warm up.

The app offered a Warm Awake feature, which would prompt the mattress to start warming up about 30 minutes before a scheduled wakeup time — allegedly a more natural way to wake up than to a buzzing alarm.

I wasn’t expecting much other than a more comfortable falling-asleep process, but the OOLER app’s programmable sleep schedule ensured that I not only fell asleep quickly but stayed asleep until it was time to wake up. I awoke after that first night feeling surprisingly refreshed. Would this trend continue? I was anxious to find out.

After three weeks of use

I’m not going to lie, the idea of water circulating around something sitting directly atop my mattress didn’t exactly fill me with ease; I tend to be an active sleeper and worried that I would disrupt something and cause a leak, but that never came to pass. The washable mattress pad cover came in handy. Yes, I ate soup in my bed and spilled. Don’t judge me.

The Warm Awake feature offered through the app produced less-than-reliable results; the shift in temperature wasn’t quite enough to rouse me, though thankfully I had set an alarm as a backup just in case. While it’s a good thing the OOLER system lulled me into a deep sleep, it was equally good to know that the system might not be able to rouse me in quite the same fashion.

What users say

The ChiliSleep website shows the OOLER Sleep System has a 4.2/5-star rating with over 800 reviews (830 at the time of publication). Here’s the breakdown:

  • 543 five-star reviews (65%)
  • 115 four-star reviews (14%)
  • 36 three-star reviews (4%)
  • 39 two-star reviews (5%)
  • 97 one-star reviews (12%)

Overall, Amazon reviewers were wowed by the OOLER Sleep System, praising it for alleviating hot flashes and night sweats all year round. Most of the reviews under 3 stars appeared to be more about user error than the system’s functionality. Here’s the breakdown of their 242 reviews:

  • 87 five-star reviews (56%)
  • 25 four-star reviews (11%)
  • 23 three-star reviews (7%)
  • 23 two-star reviews (7%)
  • 84 one-star reviews (19%)

What others say

SleepGadgets mentioned the sound the OOLER unit makes  even on silent mode  could be disruptive to light sleepers or to those who sleep in an echo-y bedroom or don’t like white noise. GQ praised the OOLER sleep system for its remarkable cooling technology, which made a summer in New York City feel bearable.

Final thoughts

For me, the OOLER system delivered on its promise to provide a long, restful night’s sleep. The ability to automate the mat’s temperature to a comfortable range, and the capability to keep both cold- and warm-blooded sleepers comfortable has easily made it something I can’t imagine sleeping without. At $699 for the half queen size, the ChiliSleep OOLER Sleep System should make anyone’s list of must-try sleep solutions.

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