In 2026, the top DIY cold-climate mini splits hit efficiency ratings up to 24...

https://www.grandmashousediy.com/best-diy-cold-climate-mini-split-hyper-heat-models-compared-mrcool-vs-cooper-hunter-vs-zone-air-2026/

In 2026, the top DIY cold-climate mini splits hit efficiency ratings up to 24 SEER2 and operate reliably down to -22°F. Most systems support line sets from 8 to 75 feet, perfect for varied layouts