Does Quilt work in the cold? Here’s the proof.

If you’ve seen a Quilt ad and thought “that looks like a California product,” you’re half right. We design Quilt in Redwood City, California, so it’s fair to wonder how it holds up in a Boston or Toronto winter. It’s the question we hear most this time of year, from homeowners and from the HVAC pros who install for them.

The short answer: Quilt is made for the cold. It delivers 100% of its rated heating capacity down to −5°F, keeps heating down to −15°F, and is Energy Star Cold Climate certified. Below, we’ll walk through the numbers, how Quilt saves energy all winter, and what homeowners say after a winter with it.

Full heating power at −5°F

Most heat pumps lose output as the temperature drops, right when you need heat most. Quilt is built to hold it. The 2-room system delivers its full rated 18,000 BTU/h of heat all the way down to −5°F. The 3-room system actually puts out more heat at 5°F than at its 47°F rating.

That works out to 100% of rated heating capacity down to −5°F and roughly 90% down to −13°F. Quilt keeps heating all the way to −15°F, and it’s Energy Star Cold Climate certified. Full details live on our tech specs page.

One more thing most heat pumps can’t say: Quilt got more powerful after it was installed. A fall 2025 over-the-air update raised maximum heating capacity to 25,200 BTU/h on every 2-room system already in homes, with no new equipment. TechCrunch covered it.

Still efficient when it’s freezing

Heat output is half the story. The other half is what that heat costs you. Engineers measure this with coefficient of performance, or COP: how many units of heat you get for every unit of electricity you pay for.

On a mild 47°F day, Quilt’s COP is 4 on the 2-room system and 4.2 on the 3-room system. That’s four units of heat for every one you pay for. At 5°F, Quilt still delivers a COP of 2, twice the heat per unit of electricity of any electric baseboard or space heater, which top out at a COP of 1.

That’s the quiet advantage of a heat pump. A furnace or boiler burns fuel to make heat. Quilt moves heat that already exists outside, even on a frozen January morning, and brings it in.

The room you’re not in shouldn’t cost you anything

A traditional furnace heats the whole house to one temperature, including the guest room nobody has opened since Thanksgiving. Quilt heats room by room, and Auto-Away takes that a step further.

Each Quilt Indoor Unit has a built-in radar sensor that knows when a room is empty, even if someone is sitting still reading on the couch. With Auto-Away on, a room that’s been empty for 20 minutes shifts into energy-saving Away mode. Walk back in, and it returns to your settings within a few minutes. You choose which rooms use it and how long it waits.

We looked at how that plays out in real homes. In an observational study of nearly 700 Quilt homes across four seasons, rooms with Auto-Away enabled used 28% less heating and cooling energy per day on average than rooms without it.* In winter, that gap was 32%.

That matters most when heating season stretches from October to April. Every hour an empty room isn’t heated is energy you keep.

What homeowners say after a winter with Quilt

Specs tell you what a system can do. Homeowners tell you what it’s like to live with.

Single digits in the Catskills. When Wirecutter tested Quilt, it was in the middle of a Catskills winter. Here’s what the reviewer wrote on NYT Wirecutter: “As frigid as it was in the Catskills during my stay, I wasn’t worried that the Quilt unit would struggle to heat my room. There’s a lingering myth that heat pumps can’t work in cold weather, but the Quilt unit kept me cozy even as the outdoor temps dropped into the single digits.”

A snowed-in Airbnb in Bedford, New York. The Perch is a woodland cottage an hour north of New York City, with guests coming up from the city and from out of state. Its hosts replaced an old through-the-wall air conditioner and noisy, inefficient heaters with two Quilt Indoor Units, including one that fits under the slanted roofline of an upstairs bedroom. When we filmed there last February, the snow was so deep our crew needed snowshoes to reach the outdoor unit.

The hosts check the temperature in the Quilt App before each guest arrives, and guests figure out the Quilt Dial on their own. “They don’t have to call me or text me asking me how to use it,” the host told us. “Very intuitive.”

Right after last winter, 93% of Quilt customers said they were satisfied. We survey Quilt homeowners twice a year. In our March 2026 survey, fielded as last winter wound down, 93% of 105 respondents were very or somewhat satisfied with their system. For comparison, only 66% of U.S. and Canadian homeowners say they’re satisfied with the HVAC they have now, according to our heat pump perceptions research. And 55% of Quilt homeowners who lived in the same home a year earlier said their combined utility bills were lower.

What’s normal on a cold morning

If this is your first winter with a heat pump, a few things will feel different from a furnace. All of them are by design.

• It runs steadily instead of blasting on and off. Quilt’s variable speed compressor adjusts its output to match what each room needs. Long, quiet run times are how it stays efficient.
• It pauses briefly to defrost. In cold, damp weather, frost can build on the outdoor unit. Quilt senses it and clears it automatically, then goes right back to heating. You may see a “preparing” status in the Quilt App while it does.
• Your partner sizes it for your winter, not an average one. Every Quilt system is designed and installed by a Quilt Certified Partner who sizes it for your home and your climate.

Get warm before the first freeze

October and November are the best months to install a heat pump in a cold climate. Partners have openings before the holiday rush, and you’re set before the first deep freeze.

Find a Quilt Certified Partner near you and start designing your system.