SplitAtlas

LG / Mega R-32

LG Mega 12k R-32 115V Mini-Split

Certified capacity
11,000 BTU/h[2]
SEER2
20 SEER2[2]
Heating floor
5 F[1]
Voltage
115V[1]
Install path
Professional install

The Mega 12k on 115V is LG's volume system: SEER2 20 on a standard circuit, certifying 11,000 BTU rather than a round 12,000 - size from the certificate. Rated to +5F, so this is a cooling-led choice. LG's cold-capable systems are the ARTCOOL Deluxe (-31F) and the LGRED-badged lines; the Mega name signals volume pricing, not winter performance.

1 zoneProfessional installCurrent

Refrigerant generation

R-32 - current-generation refrigerant

This system's warranty depends on licensed installation — get quotes from installers in your area.

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Error Codes
LG Mega R-32 12,000 BTU (115V) mini-split heat pump indoor wall unit and outdoor condenser

Image: HVACDirect

Data completeness: 95%
Last sourced
Jul 23, 2026

SplitAtlas score

8.0 / 10

Methodology
Cooling efficiencyBelow average

(20.0 SEER2) among 12k systems

Heating efficiencyBottom quartile

(9.0 HSPF2) among 12k systems

Cold-weather performanceBelow average

(76.4% heat retained at 5F; 5 F heating floor) among 12k systems

NoiseTop quartile

(-42 dBA indoor min / 50 dBA outdoor) among 12k systems

WarrantyAbove average

(10 yr parts / 10 yr compressor) across the catalogue

Feature setBelow average

(4 verified features) across the catalogue

Documentation & partsTop quartile

(9 manuals; spec sheet; 51 error-code rows) across the catalogue

Not evaluated

  • Installation accessibility — not applicable (professional install)N/A

    professional install - DIY-accessibility not applicable

  • Price-to-value — not evaluatedN/A

    This is a professionally installed, quote-only system, so we can't score its price. Get an installed quote to compare real cost.

    Get a quote

Key ratings

Rated cooling

11,000BTU/h[2]

Rated heating

11,000BTU/h[2]

Buyer review snapshot

Install difficulty

Professional install
  • Electrical: 115V; MCA 15 A; breaker/fuse 20 A.
  • Line set: connection type not sourced; precharged 24.6 ft; max 49.2 ft.

Alternatives

Availability and price context

  • Verified current price: $1,259.00 at HVACDirect; availability in_stock; checked Jul 23, 2026. Dealer-installation condition: The online source must be expressly authorized by LG; the system must also satisfy LG's qualified-system installation terms..

Purchase channel policy

LG allows the online-purchase path only when the online source is expressly authorized by LG; an online purchase from a non-authorized source voids the limited warranty.

Warranty impact
The limited warranty is void and LG has no liability when the system is purchased online from a source not expressly authorized by LG.
Installation condition
The online source must be expressly authorized by LG; the system must also satisfy LG's qualified-system installation terms.
Authorized channel
Expressly authorized LG source with qualified installation by a trained, licensed HVAC contractor under LG warranty terms.

Buying online can keep warranty coverage only when the seller is expressly authorized by LG; confirm that status and the qualified installation path before purchase.

Compare online-purchase warranty rules by brand

Source: LG Electronics U.S.A., Inc.: LG R32 Residential / Light Commercial Systems Warranty Card; retrieved Aug 15, 2026.

Source date

Model data sourced
Jul 23, 2026
Page reviewed
Jul 23, 2026
Source-backed records
4
Newest source retrieved
Jul 23, 2026

Warranty tiers

Warranty: 5 years parts and 7 years compressor as standard; 10 years parts and compressor if qualified registered installation.

Review methodology

Strengths

  • SEER2 20 on a standard 115V circuit, keeping install cost down.

Weaknesses

  • Certifies 11,000 BTU, not 12,000.
  • +5F heating floor - Mega is not a cold-climate line.

Climate suitability

Minimum heating ambient
5 F[1]
Rated heating at 5F
8,400 BTU/h[2]
Rated heating at 17F
8,000 BTU/h[2]
Rated heating at 47F
11,000 BTU/h[2]

Specifications

Show
Manufacturer
LG
Brand
LG
Product line
Mega R-32
Model number
KNSAC121B indoor / KUSAC121B outdoor
Indoor unit model
KNSAC121B
Outdoor unit model
KUSAC121B
Number of zones
1
Max indoor units
not published
Rated cooling capacity
11,000 BTU/h[2]
Rated heating capacity
11,000 BTU/h[2]
Voltage
115V[1]
MCA
15 A[1]
Maximum fuse or breaker size
20 A[1]
Breaker needed
not published
SEER2
20 SEER2[2]
EER2
12.3 EER2[2]
HSPF2 (Region 4)
9 HSPF2[2]
HSPF2 (Region 5)
not published
COP
not published
COP at 47F
not published
COP at 5F
1.8 COP[2]
Minimum outdoor heating temperature
5 F[1]
Minimum outdoor cooling temperature
14 F[1]
Maximum outdoor temperature
118 F[1]
Indoor noise range
cooling 21-42; heating 28-42 dB(A)[1]
Outdoor noise rating
50 dBA[1]
Indoor weight
19.2 lb[1]
Outdoor weight
55.3 lb[1]
Refrigerant
R-32[2]
Refrigerant charge
24.64 oz[1]
Manufacturer coverage
not published
Line-set size
1/4 in liquid / 3/8 in suction
Included line-set length
LG publishes field-supplied flared line sizes, standard/pre-charge length, and line limits; no included consumer line-set length is published for the professional system.
Maximum line-set length
49.2 ft[1]
Max line set per indoor
not published
Maximum elevation difference
23 ft[1]
Max height between indoor units
not published
Wi-Fi support
supported[1]
Energy Star status
ENERGY STAR certified[3]
AHRI certification number
214931172[2]
Warranty
Standard: 5 yr parts / 7 yr compressor (standard coverage); Best case: 10 yr parts / 10 yr compressor (qualified registered installation). Standard 5-year parts and 7-year compressor coverage; qualified registered installations extend to 10 years total parts and compressor coverage.
Install path
Professional install
Retail price
last seen at HVACDirect: $1,259.00
Available retailers
HVACDirect
Manual links
AHRI Directory public detail record 214931172, ENERGY STAR exact-match query for KUSAC121B/KNSAC121B, LG Mega 115V R-32 engineering manual, LG Mega 115V R-32 installation manual, LG HVAC API product metadata KSSAC121B, HVACDirect exact product page KSSAC121B, LG official support pages: [LG Air Conditioner] Guide to Error Codes; [LG Air Conditioner] How to Check Air Conditioner Error Codes; LG status-display help articles; LG Korea [LG Air Conditioner] Air conditioner error inquiry cross-check, KSSAC121B LG Mega 115V R-32 submittal, LG R32 Residential / Light Commercial Systems Warranty Card
Specification sheet
KSSAC121B LG Mega 115V R-32 submittal
Last sourced date
Jul 23, 2026

Retail purchase context

Dealer-installation warranty note

Buying online can keep warranty coverage only when the seller is expressly authorized by LG; confirm that status and the qualified installation path before purchase.

Installation condition: The online source must be expressly authorized by LG; the system must also satisfy LG's qualified-system installation terms.

Dealer path: Expressly authorized LG source with qualified installation by a trained, licensed HVAC contractor under LG warranty terms.

Some retailer links may earn us a commission at no extra cost; paid relationships never change scores or recommendations. Affiliate disclosure

Paid link

Dealer-installation warranty note

Buying online can keep warranty coverage only when the seller is expressly authorized by LG; confirm that status and the qualified installation path before purchase.

Check price at HVACDirect

Last seen at HVACDirect: $1,259

Electrical requirements

Show
Voltage
not published
Voltage range
115V[1]
Phase
1[1]
Frequency
60 Hz[1]
MCA
15 A[1]
Breaker needed
not published
Maximum breaker size
20 A[1]
Maximum fuse size
not published
Maximum cooling current
not published
Maximum heating current
not published
Manufacturer wire notes
14 AWG minimum four-conductor indoor-outdoor connection cable; field supplied[1]

Installation considerations

Show
Liquid line
1/4 in[1]
Suction line
3/8 in[1]
Line connection type
not published
Precharged length
24.6 ft[1]
Included line-set length
LG publishes field-supplied flared line sizes, standard/pre-charge length, and line limits; no included consumer line-set length is published for the professional system.
Maximum line-set length
49.2 ft[1]
Max line set per indoor
not published
Max height between indoor units
not published
Indoor dimensions
not published
Outdoor dimensions
not published
Indoor weight
19.2 lb[1]
Outdoor weight
55.3 lb[1]
Drain size
not published

Related systems and guides

Frequently asked questions

Can I install the LG Mega R-32 12,000 BTU (115V) myself, or do I need a pro?
LG Mega R-32 12,000 BTU (115V) is built for professional installation: the line set must be flared, evacuated, and charged, which requires EPA-certified refrigerant handling. Installing it outside the manufacturer's requirements can void the warranty, so budget for a qualified HVAC installer.
Will the LG Mega R-32 12,000 BTU (115V) keep heating in a cold winter?
The manufacturer publishes 8,400 BTU/h of heating output at 5F. Rated heating operation extends down to 5 F. Certified heating efficiency is 9 HSPF2. Match those numbers against your climate's design temperature - in cold regions, output at 5F matters far more than the nameplate capacity measured at 47F.
What electrical circuit does the LG Mega R-32 12,000 BTU (115V) need?
Published electrical requirements: 115V voltage, 15 A minimum circuit ampacity, and 20 A maximum breaker or fuse sizing. Confirm the final circuit against the unit nameplate and local code with a licensed electrician.
How far can the outdoor unit be from the indoor head?
The published maximum line-set length is 49.2 ft, and the included line set comes pre-charged for 24.6 ft. Longer runs than the included set allows typically mean added refrigerant and a pro visit, so measure the planned routing before ordering.
What warranty does the LG Mega R-32 12,000 BTU (115V) carry?
The manufacturer publishes these warranty tiers: Standard: 5 yr parts / 7 yr compressor (standard coverage); Best case: 10 yr parts / 10 yr compressor (qualified registered installation). Registration requirements and proof of qualified installation commonly affect coverage, so read the warranty terms before install day.

Data sources

Show
  1. LG Electronics U.S.A., Inc.: KSSAC121B submittalSourced - manufacturer technical document

    Covers Frequency, electrical_spec.guaranteed_voltage_range, Maximum breaker size, Minimum circuit ampacity, Phase, Manufacturer wire notes and more

  2. AHRI: AHRI Directory public detail record 214931172Sourced - AHRI directory

    Covers AHRI certification number, Rated cooling capacity, COP at 5F, EER2, Rated heating capacity, HSPF2 (Region 4) and more

  3. ENERGY STAR: ENERGY STAR exact-match record for KUSAC091A/KNSAC091ASourced - secondary source

    Covers Energy Star status

  4. LG Electronics U.S.A., Inc.: LG R32 Residential / Light Commercial Systems Warranty CardSourced - manufacturer technical document

    Covers Best-case compressor warranty, Best-case warranty conditions, Best-case parts warranty, Legacy compressor warranty value, Legacy warranty value, Standard compressor warranty and more

Last updated

Jul 23, 2026