Air conditioning

Air conditioning buying guides

Cooling ranges from a few hundred dollars for a window unit to five figures for an installed central heat pump. Ductless mini-splits sit in between, and they're often the answer for additions, garages and homes without ducts. Getting the size right matters more than the brand, so start there.

Calculator

Mini-split sizing guide: what BTU do I need? (with calculator)

ENERGY STAR's sizing chart and adjustments in a free calculator, three worked examples, what a Manual J load calculation adds, and when the law requires an EPA-certified technician.

Coming next

Mini-split vs central heat pump: costs, efficiency ratings (SEER2/HSPF2) and installation
"DIY" mini-splits: what pre-charged line sets do and don't change
Window vs portable vs saddle-style room units

Safety note: connecting or disconnecting refrigerant lines on a mini-split requires an EPA Section 608 certified technician, and most systems need a dedicated circuit. See the details and sources.

Heating too? See heating (coming soon).