Chilipad Cube Bed Cooling System, Cooling & Heating Mattress Topper, 60-115°F, Cal King (72"x84"), Model CP516 Review (2026)

Who this Cal King pad fits

The Chilipad Cube line from Sleepme, formerly Chilisleep, is built around one water-filled pad that lays over the mattress and connects to a control unit that heats or cools the circulating water. This Model CP516 is sized specifically for a California King mattress at 72 by 84 inches, so it fits shoppers who already own a Cal King bed and want a pad cut to that exact footprint rather than trimming a standard king pad to fit. It suits sleepers who want one system that handles both ends of the temperature range, hot summer nights and cold winter ones, instead of buying a cooling pad and a separate electric blanket. Because the guide's own notes describe this size as controlled from one shared setting, couples who each want independent left and right temperatures should compare it against dual-zone alternatives before buying.

How the water-based system works

Rather than using fans or thermoelectric plates, the Chilipad Cube circulates water through a network of thin silicone tubes inside the mattress pad, with the Cube control unit chilling or warming that water and pumping it through in a loop. The temperature range spans 60 to 115 degrees Fahrenheit, wide enough to actively cool a hot bed in summer or add warmth on a cold night, and adjustments are made through a control unit or remote rather than an app-only interface. The pad itself has a reversible design: one side is a breathable mesh knit built from 100 percent polyester for maximum cooling contact, while the other is a quilted cotton-polyester blend meant for more traditional all-season comfort, so owners can flip the pad depending on the season.

Setup, water top-ups, and washing

Sleepme describes the Cube system as installing in minutes, with elastic straps that stretch to fit mattresses of different heights so it sits over an existing mattress like a fitted topper. Because the system moves water rather than air, the control unit needs to stay filled, and like other Sleepme water-based pads it benefits from distilled water to avoid mineral buildup inside the tubing over time. The pad itself is listed as fully machine washable and dryable, which is a genuine advantage over some cooling pads that require spot cleaning only, letting owners run it through a normal wash cycle when needed. Because this is a large Cal King pad, expect the control unit to sit on the floor or a nearby surface rather than a small nightstand, and budget space for the tubing that connects it to the bed.

Where it lands against other cooling systems

In the site's Best Bed Cooling Systems guide this Cal King Chilipad Cube ranks last of nine, behind the King-size Chilipad Cube, the BedJet 3, both Sleepme OOLER sizes, and the Sleepme Dock Pro, all of which post higher scores across fit for the job and value. Part of that gap comes from the guide's own note that this size shares one temperature setting across the whole large bed rather than offering independent zones the way some rivals do, which matters more on a Cal King than on a smaller mattress since there is more surface for two sleepers to disagree over. Shoppers who want independent zone control on a big bed should look at the dual-zone King Chilipad Cube or a Sleepme OOLER pair instead, while single sleepers or couples who share temperature preferences may not notice the difference.

Verdict and who should consider a different model

The Chilipad Cube Cal King delivers a genuinely wide heating and cooling range in a machine-washable, water-based pad sized correctly for a large mattress, which makes it a reasonable single-system choice for one temperature setting across the whole bed. Our score of 7.8 out of 10 reflects solid marks for fit for the job, features, and build, with value at 7 out of 10 given the ongoing water maintenance the system requires. Couples on a Cal King who want separate temperatures on each side of the bed should compare this against the guide's higher-ranked, zone-capable rivals before buying, since this model is built around one shared setting for the whole mattress rather than a split configuration.

Frequently asked questions