For 2026, MRCOOL’s 24 SEER2 tops Zone Air’s 23 SEER2, but the real choice is...

https://oliviamaids.com/can-a-multi-zone-diy-system-heat-and-cool-a-whole-house/

For 2026, MRCOOL’s 24 SEER2 tops Zone Air’s 23 SEER2, but the real choice is heating range: choose MRCOOL for value above -15°F, or Zone Air Hyper Heat for performance down to -22°F.