24,000 BTU mini-split heat pump · A-series
Comfort-Aire A-KMH24SU-1
Below average cooling efficiency and very good heating efficiency for a 24,000 BTU mini-split heat pump, and certified for cold climates.
Ranks #234 of 430 24,000 BTU mini-splits for cooling efficiency, and costs about $640 a year to run in a mixed climate like Atlanta.
- SEER2
- 21.5 Cooling efficiency over a seasonBelow average · beats 39%
- HSPF2
- 11.4 Heating efficiency over a seasonVery good · beats 82%
- EER2
- 13.0 Cooling efficiency on a 95°F dayAverage · beats 62%
- Heat at 5°F
- 25,000 BTU/h86% of its 47°F outputVery good · beats 81%
A good fit if…
- Your winters get properly cold - it is ENERGY STAR cold-climate certified, with 25,000 BTU/h at 5°F.
- It will heat most of the year - its HSPF2 beats 82% of mini-splits.
- You want steady temperatures and quiet running - the compressor varies its speed.
Think twice if…
- Cooling cost matters most - its SEER2 is below average for mini-splits.
- You want the newest refrigerant - it uses R-410A, which is being phased down.
Details
Specifications
| General | |
|---|---|
| Brand | Comfort-Aire |
| Also sold as | KERR |
| Outdoor unit model | A-KMH24SU-1 |
| Series | A-series |
| Type | Mini-split heat pump |
| Nominal size | 24,000 BTU |
| CompressorVariable-speed units run longer at low power | Continuously variable |
| Refrigerant | R-410A |
| Connected (smart) capable | No |
| On the market since | December 18, 2019 |
| Last certified | June 13, 2026 |
| Cooling | |
| SEER2Seasonal efficiency, higher is better | 21.5 (range 18.9-21.5) |
| EER2Efficiency at 95°F outdoors | 11.7-13.0 |
| Cooling capacity | 21,600-24,000 BTU/h |
| Heating | |
| HSPF2Seasonal efficiency, higher is better | 10.4-11.4 |
| Capacity at 47°F | 23,400-29,000 BTU/h |
| Capacity at 17°F | 19,400-21,200 BTU/h |
| Capacity at 5°F | 23,400-25,000 BTU/h |
| COP at 5°F2.0 = twice as efficient as a space heater | 1.89-2.21 |
| ENERGY STAR cold climate | Yes |
Heating output as it gets colder
Every heat pump delivers less heat as the outdoor temperature drops. Certified output of its matchup with B-KMH24SV-1 at the standard test temperatures, in BTU/h:
Certified matchups
The same outdoor unit scores differently with each indoor unit. Ask your installer for the AHRI reference number of the exact system you are quoted.
| Indoor unit | SEER2 | EER2 | HSPF2 | Heat @5°F | AHRI ref. |
|---|---|---|---|---|---|
| B-KMH24SV-1 COMFORT-AIRE · cold climate | 21.5 | 13.0 | 11.4 | 25,000 | 208141189 |
| B-KMH24SV-1 KERR · cold climate | 21.5 | 13.0 | 11.4 | 25,000 | 208141201 |
| B-KMH24SV-1 Comfort Aire · cold climate | 21.5 | 13.0 | 11.4 | 25,000 | 217101875 |
| B-KMH24SU-1A KERR · cold climate | 18.9 | 11.7 | 10.4 | 23,400 | 206913573 |
Same unit, other model numbers
These model numbers have exactly the same certified ratings and matchups as the Comfort-Aire A-KMH24SU-1: the same equipment under another brand, or a variant code for voltage, colour or market. Everything on this page applies to them.
- Comfort-Aire A-VMH24SU-1
Yearly running cost in 10 large cities
- Phoenix, AZ$672/yr
- Miami, FL$527/yr
- Houston, TX$603/yr
- Atlanta, GA$640/yr
- Los Angeles, CA$630/yr
- New York, NY$1,568/yr
- Chicago, IL$1,280/yr
- Denver, CO$1,070/yr
- Seattle, WA$662/yr
- Minneapolis, MN$1,327/yr
At each state's average electricity price and the city's typical heating and cooling hours.
Questions
- What is the SEER2 rating of the Comfort-Aire A-KMH24SU-1?
- The Comfort-Aire A-KMH24SU-1 is rated at up to 21.5 SEER2 and 13.0 EER2 for cooling and up to 11.4 HSPF2 for heating. The exact figure depends on the indoor unit it is paired with; across its 4 certified matchups SEER2 ranges from 18.9-21.5.
- Is the Comfort-Aire A-KMH24SU-1 good for cold climates?
- Yes. At least one certified matchup meets the ENERGY STAR cold-climate criteria, delivering up to 25,000 BTU/h at 5°F with a COP of 2.21, so it is still 2.2 times as efficient as electric resistance heat at that temperature.
- How much does the Comfort-Aire A-KMH24SU-1 cost to run per year?
- At its rated efficiency it costs about $527-$1,568 a year in electricity in large U.S. cities, depending on climate and local rates - for example $672 in Phoenix and $1,327 in Minneapolis. The calculator on this page works it out for your city and compares it with your current system.
- Is the Comfort-Aire A-KMH24SU-1 the same as the Comfort-Aire A-VMH24SU-1?
- Yes, as far as the certified ratings go. ENERGY STAR lists both model numbers with identical efficiency, capacity and matchups, which means the same outdoor unit sold under a different brand or with a minor variant code (voltage, colour or region). The full list is on this page.
- Which indoor units work with the Comfort-Aire A-KMH24SU-1?
- ENERGY STAR lists 4 certified combinations for this outdoor unit. The highest-rated ones use COMFORT-AIRE B-KMH24SV-1, KERR B-KMH24SV-1, Comfort Aire B-KMH24SV-1.
- What refrigerant does the Comfort-Aire A-KMH24SU-1 use?
- It uses R-410A. R-410A is being phased down under the EPA AIM Act, and new systems are moving to R-454B and R-32.
Running cost and savings
Pre-filled with this model. Pick your city and what you heat with today; everything else is optional.
Similar 24,000 BTU models
- Blueridge BMY24HH22C · cold climate21.5 SEER2 · 11.4 HSPF2
- Franklin MSH243F25MCAA · cold climate21.5 SEER2 · 11.4 HSPF2
- AI AIR CONDITIONING AO29-24N1-M1H · cold climate21.5 SEER2 · 11.4 HSPF2
- MRCOOL O-HH-24-HP-C-230A · cold climate21.5 SEER2 · 11.4 HSPF2
- ACIQ ACIQ-24ZPL-HP230B · cold climate21.5 SEER2 · 11.4 HSPF2
- TRUST AIR CONDITIONERS OAH24H/O4S4P · cold climate21.5 SEER2 · 11.4 HSPF2
- WeatherMaker 38MARBQ24AA3 · cold climate21.5 SEER2 · 11.5 HSPF2
- DuraSTAR DRA1U24S1B · cold climate21.5 SEER2 · 11.2 HSPF2
See all 430 24,000 BTU mini-splits, ranked
Source: ENERGY STAR Certified Heat Pumps (U.S. EPA), certification of June 13, 2026. How we use the data.