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      9,000 BTU mini-split heat pump · KUSXB091A

      LG KUSXB091A

      Average cooling and heating efficiency for a 9,000 BTU mini-split heat pump, and certified for cold climates.

      Ranks #251 of 395 9,000 BTU mini-splits for cooling efficiency, and costs about $267 a year to run in a mixed climate like Atlanta.

      SEER2
      22.2 Cooling efficiency over a season
      Average · beats 52%
      HSPF2
      10.6 Heating efficiency over a season
      Average · beats 65%
      EER2
      13.9 Cooling efficiency on a 95°F day
      Very good · beats 79%
      Heat at 5°F
      10,500 BTU/h95% of its 47°F output
      Very good · beats 86%

      A good fit if…

      • Your winters get properly cold - it is ENERGY STAR cold-climate certified, with 10,500 BTU/h at 5°F.
      • You want steady temperatures and quiet running - the compressor varies its speed.

      Think twice if…

      • Nothing stands out - its ratings have no weak spot for its class.

      Calculate my running cost

      Details

      Specifications9,000 BTU, R-32
      General
      BrandLG
      Outdoor unit modelKUSXB091A
      SeriesKUSXB091A
      TypeMini-split heat pump
      Nominal size9,000 BTU
      CompressorVariable-speed units run longer at low powerContinuously variable
      RefrigerantR-32
      Connected (smart) capableNo
      On the market sinceApril 8, 2026
      Last certifiedApril 17, 2026
      Cooling
      SEER2Seasonal efficiency, higher is better22.2 (range 16.4-22.2)
      EER2Efficiency at 95°F outdoors12.2-13.9
      Cooling capacity9,000 BTU/h
      Heating
      HSPF2Seasonal efficiency, higher is better10.0-10.6
      Capacity at 47°F10,100-13,500 BTU/h
      Capacity at 17°F6,400-9,400 BTU/h
      Capacity at 5°F8,800-10,500 BTU/h
      COP at 5°F2.0 = twice as efficient as a space heater1.80-2.30
      ENERGY STAR cold climateYes
      Heating output as it gets colder95% kept at 5°F

      Every heat pump delivers less heat as the outdoor temperature drops. Certified output of its matchup with KNUDB091A at the standard test temperatures, in BTU/h:

      Certified matchups4 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.
      KNUDB091A · cold climate22.213.910.010,400214826530
      KNUFB091A · cold climate20.212.610.48,800216778959
      KNUQB091A · cold climate20.013.210.610,100214826532
      KNUJB091A · cold climate16.412.210.410,500214826531
      Yearly running cost in 10 large cities$193-$676

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

      Questions5
      What is the SEER2 rating of the LG KUSXB091A?
      The LG KUSXB091A is rated at up to 22.2 SEER2 and 13.9 EER2 for cooling and up to 10.6 HSPF2 for heating. The exact figure depends on the indoor unit it is paired with; across its 4 certified matchups SEER2 ranges from 16.4-22.2.
      Is the LG KUSXB091A good for cold climates?
      Yes. At least one certified matchup meets the ENERGY STAR cold-climate criteria, delivering up to 10,500 BTU/h at 5°F with a COP of 2.30, so it is still 2.3 times as efficient as electric resistance heat at that temperature.
      How much does the LG KUSXB091A cost to run per year?
      At its rated efficiency it costs about $193-$676 a year in electricity in large U.S. cities, depending on climate and local rates - for example $260 in Phoenix and $581 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 LG KUSXB091A?
      ENERGY STAR lists 4 certified combinations for this outdoor unit. The highest-rated ones use KNUDB091A, KNUFB091A, KNUQB091A.
      What refrigerant does the LG KUSXB091A use?
      It uses 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 $269/yrYou save $244/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 LG KUSXB091A
      3. What it replaces
      4. Price replace the example with your quote
      Heat pump, per year
      $269
      Current system, per year
      $513
      You save per year
      $244
      Payback
      14.4 years
      Net after 10 years
      -$1,063

      Cooling $143Heating $127Electricity used: 1,684 kWhSaved vs. a minimum-efficiency heat pump: $131

      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.