LG · Single-Zone
~$1,990
LG Art Cool Mirror 12,000 BTU
Style-conscious rooms in mild-to-mixed climates where the Emura's look is wanted at a lower price with better efficiency.
- BTU/h
- 12k
- Volts
- 230
- Refrig.
- R-32
- SEER2
- 22.5
- HSPF2
- 10.5
- Heats to
- -4°F
LGKNUAB121A / KUSAB121A
LG · Single-Zone
LG High Efficiency 12,000 BTU
KNUAB121A / KUSAB121A
~$1,980approximate retailer price at last check, equipment only
- BTU/h
- 12k
- Volts
- 230
- Zones
- 1
- SEER2
- 22.5
- HSPF2
- 10.5
- Heats to
- -4°F
- Refrig.
- R-32
- Covers
- 550 ft²
- Wi-Fi
- Built in
Best forModerately cold climates where 5°F is the realistic design low.
Overview
LG's High Efficiency line sits between the Mega and the LGRED units. The 12k is certified 22.5 SEER2, 12.8 EER2 and 10.5 HSPF2 (AHRI 215413007), heats 13,600 BTU at 47°F, and a device-record listing of the ENERGY STAR Most Efficient certificate gives 10,000 BTU at 5°F at a COP of 2.0. LG's own operating range for the outdoor unit is -4°F to 65°F in heating, which is the limit to plan around: this is a good heat pump to about 5°F, not a -20°F unit. At $1,980 it sells for about $180 less than the LGRED 12k, which makes the LGRED the better pick for anyone whose winters bottom out below zero. Wi-Fi is ready through SmartThinQ.
- 10,000 BTU listed at 5°F
- ENERGY STAR certified
- About $180 under the LGRED 12k
Cold-weather output
At 5°F it still makes 74% of its rated heat, according to the certified NEEP listing for this pairing. LG rates it to keep running down to -4°F.
- COP at 5°F
- 1.99
- Refrigerant
- R-32
- AHRI cert.
- 215413007
- ENERGY STAR cold climate
- Yes
Pairing: KUSAB121A with KNUAB121A. Checked October 8, 2026 on NEEP's ccASHP list; a different head or condenser posts different numbers.
Strengths and catches
Strengths
- +22.5 SEER2 / 10.5 HSPF2 under AHRI 215413007
- +10,000 BTU at 5°F per the cold-climate certificate listing
- +Indoor unit about 23 dB
- +Remote and install manual included
Catches
- −Heating limit is -4°F, well short of the LGRED line
- −The LGRED 12k costs only about $180 more
- −Licensed install needed for the 10-year term
- −Line set not included
Questions buyers ask
How well does it heat at 5°F?+
NEEP certifies 10,000 BTU at 5°F with a COP of 1.99, down from 13,600 BTU at 47°F. That is roughly 74% of its mild-weather output. It is ENERGY STAR cold climate listed.
Can it be the only heat in a place where it drops below zero?+
LG's own heating range runs from -4°F to 65°F, so below -4°F the unit is outside its stated limits. It suits climates where 5°F is the realistic design low. For sub-zero winters the LGRED 12k, rated to -31°F, is the better fit.
Is it worth choosing over the LGRED 12k?+
It costs $1,980 against $2,162, a gap of about $182. The LGRED adds a much lower operating limit, so buyers with cold winters tend to find the difference small. In a moderate climate the High Efficiency saves that money without losing much.
What size room is it for?+
Coverage is listed at 550 sq ft. The indoor unit is about 23 dB, which is quiet enough for a bedroom.
What are the install and warranty conditions?+
The 10-year warranty requires a licensed installer and registration within 60 days. The line set is not included and comes in 15 to 50 ft lengths. R-32 is an A2L refrigerant, so use someone trained to handle it.
Similar systems
Everything from LG
Series photoLG · Single-Zone
~$2,017
LG Art Cool Deluxe LGRED 9,000 BTU
Small, cold bedrooms and offices where one 9k head has to be the main heat.
- BTU/h
- 9k
- Volts
- 230
- Refrig.
- R-32
- SEER2
- 27
- HSPF2
- 13.5
- Heats to
- -31°F
Series photoLG · Single-Zone
~$1,838
LG Mega 18,000 BTU
Open living areas up to about 900 sq ft in mild or moderate climates.
- BTU/h
- 18k
- Volts
- 230
- Refrig.
- R-32
- SEER2
- 21
- HSPF2
- 9.4
- Heats to
- 5°F