Air conditioning in the United States: equipment, states, rules
Central AC, heat pumps, mini-splits, window and portable units — sized by the BTU math, judged by SEER2, priced in honest ranges. Then your state: DOE climate zone, cooling degree days, regional efficiency minimums and incentives.
Equipment
Central ACCentral AC explained for US homes: SEER2 minimums by region, honest replacement cost ranges, duct realities, a…Heat pumpUS heat pump guide: how air-source units cool and heat, honest installed cost ranges, cold-climate performance…Mini-splitDuctless mini-splits for US homes: honest cost per zone, where they beat central AC, sizing without oversizing…Window ACWindow air conditioners done right: BTU sizing by room, why U-shaped inverter units changed the game, install …Portable ACPortable air conditioners rated honestly: SACC vs ASHRAE BTU, single vs dual hose, real-world cooling losses, …
By state
- Alabama
- Alaska
- Arizona
- Arkansas
- California
- Colorado
- Connecticut
- Delaware
- Florida
- Georgia
- Hawaii
- Idaho
- Illinois
- Indiana
- Iowa
- Kansas
- Kentucky
- Louisiana
- Maine
- Maryland
- Massachusetts
- Michigan
- Minnesota
- Mississippi
- Missouri
- Montana
- Nebraska
- Nevada
- New Hampshire
- New Jersey
- New Mexico
- New York
- North Carolina
- North Dakota
- Ohio
- Oklahoma
- Oregon
- Pennsylvania
- Rhode Island
- South Carolina
- South Dakota
- Tennessee
- Texas
- Utah
- Vermont
- Virginia
- Washington
- West Virginia
- Wisconsin
- Wyoming
Guides
- SEER2 explained: what the rating means on your bill
- Heat pump vs air conditioner: the real decision framework
- Central AC replacement cost: an honest 2026 breakdown
- Mini-split vs central air: which architecture fits your house
- HVAC tax credits and rebates: claiming what you are owed
- BTU sizing guide: matching cooling power to real rooms
- Window vs portable AC: the room-cooling showdown