HVAC Rated

18,000 BTU mini-split heat pump · KUSXA181A

LG KUSXA181A

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

Ranks #377 of 465 18,000 BTU mini-splits for cooling efficiency, and costs about $504 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
13.2 Cooling efficiency on a 95°F day
Average · beats 69%
Heat at 5°F
24,000 BTU/h100% of its 47°F output
Average · beats 48%

A good fit if…

  • Your winters get properly cold - it is ENERGY STAR cold-climate certified, with 24,000 BTU/h at 5°F.
  • You want steady temperatures and quiet running - the compressor varies its speed.
  • You want a choice of indoor units - 10 certified pairings.

Think twice if…

  • Cooling cost matters most - its SEER2 is below average for mini-splits.

Calculate my running cost

Details

Specifications18,000 BTU, R-32
General
BrandLG
Outdoor unit modelKUSXA181A
SeriesKUSXA181A
TypeMini-split heat pump
Nominal size18,000 BTU
CompressorVariable-speed units run longer at low powerContinuously variable
RefrigerantR-32
Connected (smart) capableNo
On the market sinceDecember 2, 2024
Last certifiedSeptember 22, 2026
Cooling
SEER2Seasonal efficiency, higher is better20.5 (range 15.2-20.5)
EER2Efficiency at 95°F outdoors11.5-13.5
Cooling capacity17,000-18,000 BTU/h
Heating
HSPF2Seasonal efficiency, higher is better8.1-10.0
Capacity at 47°F20,000 BTU/h
Capacity at 17°F12,900-13,600 BTU/h
Capacity at 5°F17,000-24,000 BTU/h
COP at 5°F2.0 = twice as efficient as a space heater1.80-2.00
ENERGY STAR cold climateYes
Heating output as it gets colder100% kept at 5°F

Every heat pump delivers less heat as the outdoor temperature drops. Certified output of its matchup with KNUDB181A at the standard test temperatures, in BTU/h:

Certified matchups10 indoor units

The same outdoor unit scores differently with each indoor unit and furnace. Ask your installer for the AHRI reference number of the exact system you are quoted.

Indoor unitFurnaceSEER2EER2HSPF2Heat @5°FAHRI ref.
KNUDB181A · cold climate-20.513.29.520,000214825952
KNSFB181A · cold climate-20.012.59.517,000216592037
KNUFB181A · cold climate-20.012.59.517,000216778956
KNSLA181A · cold climate-18.013.510.024,000215588567
KNSLA181A · cold climate-18.013.510.024,000217284907
KNUJB181A · cold climate-17.512.49.220,000214796350
LKMMA18B1 · cold climateLNA**060B117.011.59.519,000217284946
LKMMA18B1 · cold climateLNAEA080B117.011.59.519,000218770189
LKMMA18A1 · cold climate-15.211.58.118,000216445254
LKMMA18B1 · cold climate-15.211.58.118,000216445255
Yearly running cost in 10 large cities$415-$1,233

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 KUSXA181A?
The LG KUSXA181A is rated at up to 20.5 SEER2 and 13.2 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 10 certified matchups SEER2 ranges from 15.2-20.5.
Is the LG KUSXA181A good for cold climates?
Yes. At least one certified matchup meets the ENERGY STAR cold-climate criteria, delivering up to 24,000 BTU/h at 5°F with a COP of 2.00, so it is still 2.0 times as efficient as electric resistance heat at that temperature.
How much does the LG KUSXA181A cost to run per year?
At its rated efficiency it costs about $415-$1,233 a year in electricity in large U.S. cities, depending on climate and local rates - for example $528 in Phoenix and $1,043 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 KUSXA181A?
ENERGY STAR lists 10 certified combinations for this outdoor unit. The highest-rated ones use KNUDB181A, KNSFB181A, KNUFB181A.
What refrigerant does the LG KUSXA181A 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 $533/yrYou save $428/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 KUSXA181A
3. What it replaces
4. Price replace the example with your quote
Heat pump, per year
$533
Current system, per year
$961
You save per year
$428
Payback
16.4 years
Net after 10 years
-$2,722

Cooling $309Heating $224Electricity used: 3,332 kWhSaved vs. a minimum-efficiency heat pump: $209

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 September 22, 2026. How we use the data.