SEER2 savings calculator
CoolingAnnual cooling cost and payback when you move from one SEER2 rating to another.
SEER2 · $/yr
Cooling
6 tools, 5 guides, 2 comparisons
Air conditioners, mini splits, refrigerant and SEER2 — the cool side of the manifold.
The cooling side splits into two jobs. Choosing equipment: SEER2 minimums by region (the table below), the heat pump vs air conditioner question, ductless against ducted, and room-scale sizing with the window AC and dehumidifier calculators.
Servicing what is installed: the R-410A pressure chart converts gauge readings to saturation temperatures, the superheat and subcooling calculator turns them into a charge verdict, and the AC-not-cooling guide works through the faults that are not charge at all. The R-454B guide covers what the refrigerant transition changes on the truck.
Tools
Mini split sizing calculator
CoolingBTU/h per zone and how many heads a house actually needs.
BTU/h · zones
Superheat and subcooling calculator
CoolingTarget superheat and subcooling from pressures and temperatures, with the charge verdict.
°F · psig
R-410A pressure chart
CoolingSaturation pressure by temperature for R-410A, with R-454B bubble and dew columns.
psig · °F
Window AC size calculator
CoolingRoom air conditioner BTU/h from the ENERGY STAR chart, with sun, shade and kitchen adjustments.
BTU/h · room
Dehumidifier size calculator
CoolingPints per day by room size and dampness, and old ratings converted to the 2019 test.
pints/day
SEER2 minimums
| Product class | National | Southeast / Southwest |
|---|---|---|
| Split AC, under 45,000 BTU/h | 13.4 | 14.3 |
| Split AC, 45,000 BTU/h and over | 13.4 | 13.8 |
| Split heat pump | 14.3 | national only |
| Single-package AC | 13.4 | national only |
| Single-package heat pump | 13.4 | national only |
Southeast: Alabama, Arkansas, Delaware, Florida, Georgia, Hawaii, Kentucky, Louisiana, Maryland, Mississippi, North Carolina, Oklahoma, Puerto Rico, South Carolina, Tennessee, Texas, Virginia, the District of Columbia and the U.S. Territories. Southwest: Arizona, California, Nevada and New Mexico, which also carries an EER2 floor. Regional air-conditioner standards apply at installation, not at manufacture.
Sources: 10 CFR 430.32(c)(6)(i)(A) (read 2026-09-04)
Guides
SEER2 explained
CoolingWhat changed in 2023, how SEER converts to SEER2, and the regional minimums.
9 min read
AC not cooling
CoolingRunning but not cold, frozen coil, compressor silent — a decision list.
12 min read
How often to change your filter
CoolingIntervals by filter depth and MERV, and which way the arrow points.
7 min read
HVAC zoning systems
CoolingDampers, bypass, and why a zoned system needs a variable-speed blower.
10 min read
The R-454B refrigerant transition
CoolingWhat the 2025 A2L changeover means for repairs, charging and parts.
9 min read
Comparisons
Other sections
Sizing & Load
Manual J load, BTU/h, tonnage, duct sizing and static pressure — the numbers that decide what equipment goes in.
8 tools, 4 guides
Heating
Furnaces, heat pumps and the efficiency ratings that price them — AFUE, HSPF2 and the cold-climate question.
3 tools, 5 guides
Service & Costs
Replacement cost, maintenance, filters and the credits that move the price — what the job costs and what keeps it running.
6 tools, 6 guides