Series photoLG · Single-Zone
~$1,240
LG Mega 12,000 BTU
Mild-to-moderate climates where one 12k head covers a living room or primary bedroom.
- BTU/h
- 12k
- Volts
- 230
- Refrig.
- R-32
- SEER2
- 20
- HSPF2
- 9
- Heats to
- 5°F
The maker's photo for this series, not this exact size; the outdoor unit grows with capacity
LG · Single-Zone
LG Mega 9,000 BTU
KNSAC091A / KUSAC091A
~$1,143approximate retailer price at last check, equipment only
- BTU/h
- 9k
- Volts
- 230
- Zones
- 1
- SEER2
- 21
- HSPF2
- 9.2
- Heats to
- 5°F
- Refrig.
- R-32
- Covers
- 400 ft²
- Wi-Fi
- Built in
Best forMild-climate bedrooms and small offices that want better efficiency than LG's entry line.
Overview
The Mega 9k is the step up from LG's Standard line: 21 SEER2 and 9.2 HSPF2 (AHRI 214931158) against 18 and 8.7, for about $244 more. It heats 10,900 BTU at the rating point and operates in heating down to 5°F, the same limit as the Standard. A 115V version, KSSAC091B, is also sold for about $11 more, which is the one to look at if the only available circuit is 115V. LG pitches it to rooms up to 400 sq ft. If you live where it gets below 5°F, the LGRED line is the better buy; for a bedroom in a mild climate this is the efficient one.
- 115V version available
- Quiet: 21 dB indoor
Cold-weather output
No current listing on NEEP's cold-climate heat pump list (checked October 8, 2026). LG rates it to keep running down to 5°F; without a listing there's no certified 5°F capacity figure to check that claim against.
Strengths and catches
Strengths
- +21 SEER2 / 9.2 HSPF2 under AHRI 214931158
- +115V KSSAC091B version exists
- +10-year warranty term
- +Quiet: 21 dB indoor, 50 dB outdoor
Catches
- −Heating limit of 5°F rules it out as sole heat in cold zones
- −Licensed install required for the full warranty
- −Line set not included
Questions buyers ask
What size room suits the Mega 9k?+
LG pitches it to rooms up to 400 sq ft, such as a bedroom or small office. Heating is 10,900 BTU at the 47°F rating point.
Is there a version for a 115V circuit?+
Yes, the KSSAC091B is a 115V sibling sold for about $11 more. The standard model here is 230V with a 15 to 20 A breaker. Pick the 115V one only if that is the only available circuit.
How cold can it go?+
Heating operation is listed down to 5°F, and no certified 5°F capacity is published for this model. That makes it a mild-climate or supplemental-heat unit. In places that dip below 5°F, the LGRED line is the better choice.
What does the warranty require, and what does it cost to install?+
The 10-year term needs a licensed installer and registration within 60 days. The line set is not in the box. At $1,143 the unit itself is $244 above the LG Standard 9k, whose 18 SEER2 trails this one's 21.
Similar systems
Everything from LGSeries photo
LG · Single-Zone
~$929
LG Standard 18-SEER2 12,000 BTU
Moderate-climate rooms where the goal is the lowest installed price that still comes with a real brand warranty and parts network.
- BTU/h
- 12k
- Volts
- 230
- Refrig.
- R-32
- SEER2
- 18
- HSPF2
- 8.5
- Heats to
- 5°F
Series photoLG · Single-Zone
~$899
LG Standard 9,000 BTU
Mild-climate small rooms where price and a major-brand warranty matter more than winter output.
- BTU/h
- 9k
- Volts
- 230
- Refrig.
- R-32
- SEER2
- 18
- HSPF2
- 8.7
- Heats to
- 5°F