Most efficient 24,000 BTU mini-splits (HSPF2, then SEER2)
Ranking criteria: cooling capacity in the 24,000 BTU (2 ton) class; ranked by HSPF2, then SEER2. Cost columns are estimates per 1,000 full-load hours at the U.S. average rate. Data: ENERGY STAR certification records retrieved 2026-10-17. Rankings are calculated from published ratings only. They are not hands-on tests or installations, and noise, price, warranty, installer availability and reliability are not considered (not in the data).
| # | Outdoor brand | Outdoor unit | Indoor unit | Cooling BTU/h | SEER2 | HSPF2 | Cold climate | Heat $/1,000 h | Cool $/1,000 h | Record |
|---|---|---|---|---|---|---|---|---|---|---|
| 1 | Airquest | D5CSHAH24AAK | D5FSHAH24XAK | 24,000 | 21.2 | 13.5 | Yes | $393 | $207 | 3556652 |
| 2 | Arcoaire | D5CSHAH24AAK | D5FSHAH24XAK | 24,000 | 21.2 | 13.5 | Yes | $393 | $207 | 3556064 |
| 3 | Bryant | 37MAHAQ24AA3 | 615AHAQ24XA3 | 24,000 | 21.2 | 13.5 | Yes | $393 | $207 | 3555737 |
| 4 | Bryant | 37MAHAQ24AA3 | D5MAHAQ24XA3 | 24,000 | 21.2 | 13.5 | Yes | $393 | $207 | 4573090 |
| 5 | Carrier | 37MAHAQ24AA3 | 45MAHAQ24XA3 | 24,000 | 21.2 | 13.5 | Yes | $393 | $207 | 3555726 |
| 6 | Carrier | 37MAHAQ24AA3 | D5MAHAQ24XA3 | 24,000 | 21.2 | 13.5 | Yes | $393 | $207 | 4573102 |
| 7 | Comfortmaker | D5CSHAH24AAK | D5FSHAH24XAK | 24,000 | 21.2 | 13.5 | Yes | $393 | $207 | 3556129 |
| 8 | Day & Night | D5CSHAH24AAK | D5FSHAH24XAK | 24,000 | 21.2 | 13.5 | Yes | $393 | $207 | 3556194 |
| 9 | Heil | D5CSHAH24AAK | D5FSHAH24XAK | 24,000 | 21.2 | 13.5 | Yes | $393 | $207 | 3556262 |
| 10 | Keeprite | D5CSHAH24AAK | D5FSHAH24XAK | 24,000 | 21.2 | 13.5 | Yes | $393 | $207 | 3556327 |
| 11 | Kenmore | D5CSHAH24AAK | D5FSHAH24XAK | 24,000 | 21.2 | 13.5 | Yes | $393 | $207 | 3556394 |
| 12 | LPS Legacy | D5CSHAH24AAK | D5FSHAH24XAK | 24,000 | 21.2 | 13.5 | Yes | $393 | $207 | 3556715 |
| 13 | Midea | 37MAHAQ24AA3 | D5MAHAQ24XA3 | 24,000 | 21.2 | 13.5 | Yes | $393 | $207 | 3555771 |
| 14 | Midea | D5CSHAH24AAK | D5FSHAH24XAK | 24,000 | 21.2 | 13.5 | Yes | $393 | $207 | 3556461 |
| 15 | Payne | 37MAHAQ24AA3 | D5MAHAQ24XA3 | 24,000 | 21.2 | 13.5 | Yes | $393 | $207 | 3555749 |
| 16 | SMART COMFORT | D5CSHAH24AAK | D5FSHAH24XAK | 24,000 | 21.2 | 13.5 | Yes | $393 | $207 | 3556483 |
| 17 | Tempstar | D5CSHAH24AAK | D5FSHAH24XAK | 24,000 | 21.2 | 13.5 | Yes | $393 | $207 | 3556529 |
| 18 | Viessmann | D5CSHAH24AAK | D5FSHAH24XAK | 24,000 | 21.2 | 13.5 | Yes | $393 | $207 | 4006716 |
| 19 | WEATHERMAKER | 37MAHAQ24AA3 | D5MAHAQ24XA3 | 24,000 | 21.2 | 13.5 | Yes | $393 | $207 | 3555760 |
| 20 | MDV | MOD30-24HFN10-M1X | MSEPD-24HRFN10-M1 | 24,000 | 21.2 | 13.5 | Yes | $393 | $207 | 3893400 |
| 21 | 1HVAC | ACIQ-24ZPL-HP230C | ACIQ-24W-HH-MD | 24,000 | 21 | 13.5 | Yes | $393 | $209 | 3723260 |
| 22 | ACIQ | ACIQ-24ZPL-HP230C | ACIQ-24W-HH-MD | 24,000 | 21 | 13.5 | Yes | $393 | $209 | 3723318 |
| 23 | MAINLINE | ML24HP230CALH-O | ML24HP230CALH-I | 24,000 | 21 | 13.5 | Yes | $393 | $209 | 4688160 |
| 24 | Bosch | BMS500-AAS024-1CSXHD | BMS500-AAU024-1AHWXD | 24,000 | 21 | 13.5 | Yes | $393 | $209 | 3554546 |
| 25 | Breeze33 | BZ33-HYP24OUT2-454-G3-P | BZ33-HYP24WALL2-454-G3-P | 24,000 | 21 | 13.5 | Yes | $393 | $209 | 3627324 |
| 26 | Cooper&Hunter | CH-RHP24-230VO | CH-PRO24MASTWM-230VI | 24,000 | 21 | 13.5 | Yes | $393 | $209 | 3712332 |
| 27 | Cooper&Hunter | CH-RHP24-230VO | CH-RH24MASTWM-230VI | 24,000 | 21 | 13.5 | Yes | $393 | $209 | 3712337 |
| 28 | CanAir | 4C28SCH24H21 | 4C28SEH24H21 | 24,000 | 21 | 13.5 | Yes | $393 | $209 | 3712081 |
| 29 | DIRECT AIR | DIRM4-24HXPRO28-1Z | DIRM4-24HP-WM | 24,000 | 21 | 13.5 | Yes | $393 | $209 | 3891442 |
| 30 | EMI | EMXSZ124DA | EMXWAL24DA | 24,000 | 21 | 13.5 | Yes | $393 | $209 | 3627278 |
Cost estimates: cooling kWh ≈ cooling capacity × full-load hours ÷ SEER2 ÷ 1,000; heating kWh ≈ 47°F heating capacity × full-load hours ÷ HSPF2 ÷ 1,000. "Per 1,000 full-load hours" is a yardstick for comparing systems, not a prediction of your bill; your hours depend on climate, house and settings. Rate: U.S. average residential 18.31¢/kWh (EIA, July 2026 (preliminary)).