Is KUSXB121A genuine LG equipment?

Yes. KUSXB121A sold by TotalHVACParts is genuine LG OEM equipment, not an aftermarket substitute.

LG KUSXB121A 1-Way Ceiling Cassette Perspective Front1

Photo may vary slightly — verify by model number before ordering.

LG Genuine OEM

LG KUSXB121A 12,000 BTU Single-Zone Universal Heat Pump Outdoor Unit, R32

Model KUSXB121A

Also listed under these names — same part, same manufacturer.

LG ElectronicsLG Single-Zone UniversalLG Air Conditioning Technologies

Genuine LG OEM Free ground shipping (US) Ships via UPS/FedEx Ground — expedited available No account needed

$1,753.99 per unitList $1,809.99

30-day returns

9 in stock — live count

In stock and ordered before 1pm ET, Mon–Fri? It ships the same day from our US warehouse.

Not sure it's the right unit? Send the model and serial — help@totalhvacparts.com or 302-219-4994.

Need more than 9? Ask about factory lead time — we'll give you a real date, not a guess.

Min. order: 1 unit · Weight: 79.4 lb · Truck Freight

Overview

LG KUSXB121A is a 12,000 BTU class R32 Single-Zone Universal inverter heat pump outdoor unit for LG's single-zone ducted, cassette, console and air-handler systems. LG rates it with the following indoor units: KNUFB121A, KNUDB121A, KNUQB121A, KNUJB121A, KNSLB121A (see Companion Units below for the matching system bundles). Rated 3,600 / 12,000 / 12,400 Btu/h cooling and 4,400 / 15,400 / 16,500 Btu/h heating (min / rated / max). It replaces the R-410A LUU120HV.

75 lb net, 208-230V power, 13.4 A MCA / 15 A MOP, 49 dB(A) sound pressure in cooling, heating operation down to -4°F outdoor, 11,000 Btu/h available at 5°F.

Pairing and installation

Indoor unit: LG KNUFB121A, LG KNUDB121A, LG KNUQB121A, LG KNUJB121A, LG KNSLB121A — one head per system.
Refrigerant: R32 (A2L) — installation by a licensed contractor following the LG R32 installation manual and local code.
Electrical: 208-230V, 13.4 A MCA, 15 A MOP; disconnect and breaker field supplied.

Installation and warranty registration by an LG-trained licensed contractor — current terms are in the LG limited warranty document under Documentation.

Compatible Units

LG approves KUSXB121A only in the combinations below (per the LG engineering manual and submittal). Mixing it with any other outdoor or indoor unit is not an AHRI-rated match. Ask the parts desk if your existing equipment isn't listed.

KNUFB121A (indoor unit)
KNUDB121A (indoor unit)
KNUQB121A (indoor unit)
KNUJB121A (indoor unit)
KNSLB121A (indoor unit)
KSUFB121A (system)
KSUDB121A (system)
KSUQB121A (system)
KSUJB121A (system)
KSSLB121A (system)

Specifications

Technical Data — LG OEM KUSXB121A

System Cooling Capacity (Min / Rated / Max, Btu/h)

3,600 / 12,000 / 12,400

System SEER2

21.7

System EER2

12.20

System Heating Capacity (Min / Rated / Max, Btu/h)

4,400 / 15,400 / 16,500

System HSPF2

10.1

Max. Heating at 17°F Outdoor (Btu/h)

12,700

Max. Heating at 5°F Outdoor (Btu/h)

11,000

Max. Heating at -4°F Outdoor (Btu/h)

9,800

MOP (A)

MCA (A)

13.4

Cooling Rated Amps (A)

0.8 / 4.3 / 4.8

Heating Rated Amps (A)

0.7 / 5.8 / 7.1

Compressor (A)

Fan Motor (IDU + ODU) (A)

0.58 + 0.4

Cooling Power Input (Min~Rated~Max @95°F) (kW)

0.19 / 0.984 / 1.10

Heating Power Input (Min~Rated~Max @47°F) (kW)

0.15 / 1.326 / 1.62

Liquid (ODU, in., Connection Size/Pipe Size)

1/4 / 1/4

Vapor (ODU, in., Connection Size/Pipe Size)

3/8 / 3/8

Liquid (IDU, in., Connection Pipe Size)

1/4

Vapor (IDU, in., Connection Pipe Size)

3/8

Additional Refrigerant (oz./ft.)

0.22

Max. Pipe Length (ft.)

65.6

Piping Length (no add'l refrig., ft.)

24.6

Max. Elevation (ft.)

49.2

Compressor F ODUs

• Built-in Wi-Fi via Smart

Outdoor Operating Range – Cooling (°F DB)

5 / 118

Outdoor Operating Range – Heating (°F WB)

-4 / +64

Refrigerant Type

R32

Refrigerant Control

EEV

Refrigerant Charge (lbs.)

2.43

ODU Sound Pressure – Cooling / Heating dB(A)

49 / 52

ODU Net / Shipping Weight (lbs.)

75 / 79.4

Heat Exchanger Coating

GoldFin™

ODU Type

Axial

Fan Quantity (ODU + IDU)

1 + 1

Motor/Drive Max. ODU Air Flow Rate (CFM)

988

Values in italic are not yet confirmed from OEM documentation. Ask us to verify before ordering.

Documentation

LG Submittal – SZ OneWayCassette R32 KSUFB121A

Submittal

↓ Submittal

LG Engineering Manual – SZ OneWayCassette R32

Engineering Manual

↓ Engineering Manual

LG Installation Manual – R 32 Multi Functional Outdoor Unit Installation

Installation Manual

↓ Installation Manual

LG R32 Residential & Light Commercial Limited Warranty

Warranty

↓ Warranty

LG R-410A to R-32 Model Number Crosswalk (Feb 2025)

Cross-Reference

↓ Cross-Reference

Companion Units & System Bundle

Model	Description	Stock
KNUFB121ALG · Compatible indoor unit	KNUFB121A 12,000 BTU 1-Way Ceiling Cassette indoor unit	✓ In stock	View
KSUFB121ALG · Complete system	KSUFB121A bundle: KNUFB121A indoor unit + this outdoor unit	✓ In stock	View
KNUDB121ALG · Compatible indoor unit	KNUDB121A 12,000 BTU 4-Way Ceiling Cassette indoor unit	✓ In stock	View
KSUDB121ALG · Complete system	KSUDB121A bundle: KNUDB121A indoor unit + this outdoor unit	Out of stock — contact us	View
KNUQB121ALG · Compatible indoor unit	KNUQB121A 12,000 BTU Low Wall Console indoor unit	✓ In stock	View
KSUQB121ALG · Complete system	KSUQB121A bundle: KNUQB121A indoor unit + this outdoor unit	Out of stock — contact us	View
KNUJB121ALG · Compatible indoor unit	KNUJB121A 12,000 BTU Mid-Static Ducted indoor unit	✓ In stock	View
KSUJB121ALG · Complete system	KSUJB121A bundle: KNUJB121A indoor unit + this outdoor unit	Out of stock — contact us	View

After You Order

Confirmed

Order number and confirmation by email the moment you check out.

Packed

Pulled from our shelf — the same live count you saw on this page. In-stock orders placed before 1pm ET, Mon–Fri, leave the same business day.

Shipped

Tracking number lands in your inbox the moment it leaves the building.

Delivered

Check the part number on the label against your order before installing. Wrong or damaged? Tell us — we'll sort it out.

Ask the Parts Desk

Not sure this fits? Need more than what's in stock? Send the model and serial from the unit's data plate — a real person reads it and confirms before you order.

Common Questions

What does the LG KUSXB121A pair with?

LG rates KUSXB121A only with KNUFB121A (indoor unit) or KNUDB121A (indoor unit) or KNUQB121A (indoor unit) or KNUJB121A (indoor unit) or KNSLB121A (indoor unit) or KSUFB121A (system) or KSUDB121A (system) or KSUQB121A (system) or KSUJB121A (system) or KSSLB121A (system). Other combinations are not AHRI-matched and are not covered by the LG warranty.

What does the KUSXB121A replace?

KUSXB121A is LG's current R32 model in this position and replaces the discontinued LUU120HV. R32 and R-410A equipment cannot be mixed — replace the indoor and outdoor unit together.

What power does the KUSXB121A need?

208-230V, 1-phase. Minimum circuit ampacity and maximum overcurrent protection are listed in the Specifications table above and on the LG submittal under Documentation; size the breaker and wire to those values and local code.

Is the submittal sheet and installation manual available for KUSXB121A?

Yes — the LG submittal data sheet, engineering manual, installation manual and warranty document are all linked under Documentation on this page and can be downloaded without an account.

Is the stock number on this page real?

Yes — it's the live count from our own shelf, not an availability estimate. If it says 9, that's how many are physically here. When it hits zero, this page says so.

Is this a genuine LG unit, or aftermarket?

Genuine LG OEM equipment — not an aftermarket substitute.

I see this listed under a different name on other sites. Is it the same part?

Yes — manufacturers and distributors sometimes use different brand names or legacy labels for the same part number. Part number KUSXB121A is identical across all name variations.

What's the warranty on this part?

Warranty terms vary by manufacturer. Contact us with your order number for details specific to this part.

How fast does this ship?

In-stock items ship the same business day on orders placed before 1pm ET, Monday–Friday. Standard ground delivers to most of the continental US in 2–5 business days. This part ships by LTL freight, so transit runs on the freight schedule — we'll contact you to arrange delivery.

Does everything ship UPS or FedEx Ground?

This part ships by truck freight rather than parcel — still free, included in the price shown, and we'll contact you to schedule delivery before it ships.Most orders ship UPS or FedEx Ground. A small number of large or heavy parts across the catalog ship by truck freight instead — that's still free, and we reach out to arrange a delivery window before those orders leave the warehouse.