A photo posted by a homeowner in Finland is giving fresh life to one of the internet's most persistent HVAC arguments: Do heat pumps actually work when winter gets brutally cold?

The post, shared to Reddit's r/HeatPumps forum, shows a newly installed outdoor HVAC unit surrounded by snow. 

"Here is the freshly installed heating solution for my detached garage and storage in Finland, -18C as the picture was taken," the original poster wrote. 

The image helped prove that heat pumps are still useful even when temperatures drop below freezing. Many homeowners still hear that heat pumps are only suited for mild climates. One commenter summed up that misconception with a joke.

"But I was told by r/hvac that heat pumps don't work once it gets to like 30F," they wrote.

But this homeowner's post offered a real-world snapshot of the opposite — a cold-climate system operating in subzero weather in a Nordic country where winter performance is not optional.

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Several commenters pointed out that modern cold-climate models are very different from older heat pumps. These newer inverter systems use variable-speed compressors and fans, allowing them to keep producing heat far more efficiently in low temperatures.

One Redditor cited a 2023 article on specially engineered cold-climate heat pumps, saying Business in Vancouver reported that certain Mitsubishi and Toshiba units used in Finland still have COPs above 2 at minus-20 degrees Celsius.

That means they can deliver more than twice as much heat energy as the electricity they consume. That's far better than electric resistance heating, which effectively tops out at a 1-to-1 ratio.

Heat pumps can lead to meaningful savings on energy bills. Over time, those savings can add up, especially in garages, workshops, additions, and homes that need steady heat through long winters.

There is an environmental upside, too. When households switch from fossil fuels or less efficient electric heating to a high-performance heat pump, they can pollute less while creating energy independence for themselves.

Homeowners looking to save even more can also pair efficient electric appliances with rooftop solar to push utility bills even lower.

The comments under the Reddit post captured just how quickly the old myth is fading.

"I am from Quebec, Canada and heat pumps are a must in all houses," one wrote. 

"I am in Canada lots of people use them and it gets a lot colder than that here," another person said.

To see how efficient modern targeting heating solutions are, connect with the experts at Merino. The Merino Mono is a high-tech heating and cooling unit that requires no electrical upgrades and can be installed in under an hour.

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