HVAC Rated

18,000 BTU mini-split heat pump · A series

KERR A-KMH18SU-1A

Below average cooling efficiency and average heating efficiency for a 18,000 BTU mini-split heat pump, and certified for cold climates.

Ranks #376 of 465 18,000 BTU mini-splits for cooling efficiency, and costs about $461 a year to run in a mixed climate like Atlanta.

SEER2
20.5 Cooling efficiency over a season
Below average · beats 24%
HSPF2
10.0 Heating efficiency over a season
Average · beats 43%
EER2
12.5 Cooling efficiency on a 95°F day
Average · beats 44%
Heat at 5°F
17,700 BTU/h93% of its 47°F output
Below average · beats 27%

A good fit if…

  • Your winters get properly cold - it is ENERGY STAR cold-climate certified, with 17,700 BTU/h at 5°F.
  • 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.

Calculate my running cost

Details

Specifications18,000 BTU, R-410A
General
BrandKERR
Outdoor unit modelA-KMH18SU-1A
SeriesA series
TypeMini-split heat pump
Nominal size18,000 BTU
CompressorVariable-speed units run longer at low powerContinuously variable
RefrigerantR-410A
Connected (smart) capableNo
On the market sinceDecember 18, 2019
Last certifiedApril 17, 2026
Cooling
SEER2Seasonal efficiency, higher is better20.5 (range 18.0-20.5)
EER2Efficiency at 95°F outdoors11.7-12.5
Cooling capacity16,000-17,000 BTU/h
Heating
HSPF2Seasonal efficiency, higher is better9.5-10.0
Capacity at 47°F17,000-19,000 BTU/h
Capacity at 17°F10,900-15,600 BTU/h
Capacity at 5°F16,000-17,700 BTU/h
COP at 5°F2.0 = twice as efficient as a space heater1.75-1.90
ENERGY STAR cold climateYes
Heating output as it gets colder93% kept at 5°F

Every heat pump delivers less heat as the outdoor temperature drops. Certified output of its matchup with B-KMH18UU-1 at the standard test temperatures, in BTU/h:

Certified matchups5 indoor units

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 unitSEER2EER2HSPF2Heat @5°FAHRI ref.
B-KMH18UU-1 · cold climate20.512.59.816,800206347322
B-KMH18CU-1 · cold climate20.012.59.516,000206347317
B-KMH18SU-119.412.510.016,400206913037
B-KMH18SU-1A19.412.510.016,400205747697
B-KMH18DU-1 · cold climate18.011.79.517,700206347320
Yearly running cost in 10 large cities$391-$1,119

At each state's average electricity price and the city's typical heating and cooling hours.

Questions5
What is the SEER2 rating of the KERR A-KMH18SU-1A?
The KERR A-KMH18SU-1A is rated at up to 20.5 SEER2 and 12.5 EER2 for cooling and up to 10.0 HSPF2 for heating. The exact figure depends on the indoor unit it is paired with; across its 5 certified matchups SEER2 ranges from 18.0-20.5.
Is the KERR A-KMH18SU-1A good for cold climates?
Yes. At least one certified matchup meets the ENERGY STAR cold-climate criteria, delivering up to 17,700 BTU/h at 5°F with a COP of 1.90, so it is still 1.9 times as efficient as electric resistance heat at that temperature.
How much does the KERR A-KMH18SU-1A cost to run per year?
At its rated efficiency it costs about $391-$1,119 a year in electricity in large U.S. cities, depending on climate and local rates - for example $492 in Phoenix and $943 in Minneapolis. The calculator on this page works it out for your city and compares it with your current system.
Which indoor units work with the KERR A-KMH18SU-1A?
ENERGY STAR lists 5 certified combinations for this outdoor unit. The highest-rated ones use B-KMH18UU-1, B-KMH18CU-1, B-KMH18SU-1.
What refrigerant does the KERR A-KMH18SU-1A 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.

Heat pump $494/yrYou save $399/yrSee details ↓
1. Where you live
Adjust heating and cooling hours

Filled in from your city's climate. Change them if you run the system much more or less than usual.

2. The heat pump KERR A-KMH18SU-1A
3. What it replaces
4. Price replace the example with your quote
Heat pump, per year
$494
Current system, per year
$893
You save per year
$399
Payback
16.3 years
Net after 10 years
-$2,506

Cooling $292Heating $202Electricity used: 3,084 kWhSaved vs. a minimum-efficiency heat pump: $194

Estimates use the unit's rated SEER2 and HSPF2, full-load hours derived from NOAA 1991-2020 degree days, average residential electricity prices from the U.S. EIA (12 months to July 2026) and fuel prices from EIA (2025 for natural gas, week of 2026-10-05 for propane and heating oil). Very cold days that need backup heat are not modelled. Federal minimum for comparison: 14.3 SEER2 / 7.5 HSPF2.

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Source: ENERGY STAR Certified Heat Pumps (U.S. EPA), certification of April 17, 2026. How we use the data.