How many square feet does the LG LW1822IVSM cool?

At 18,000 BTU/h it suits a room of about 700 to 1000 sq ft with normal sun and two people, following the ENERGY STAR sizing guide. In a heavily shaded room that stretches to about 770-1100 sq ft; in a very sunny one it shrinks to 630-900 sq ft. A kitchen needs 4,000 BTU more.

How many watts and amps does the LG LW1822IVSM use?

About 1224 watts at full power (18,000 BTU/h divided by its CEER of 14.7), which is 5.3 amps at 230 V. That is 26 W less than the typical unit in its class (1250 W), or $3 a year cheaper to run at 18.0¢/kWh. Its inverter compressor slows down instead of cycling, so real use is usually lower. Its CEER beats 50% of the 10 units in the class.

What outlet does the LG LW1822IVSM need?

It is a 230 V unit that draws 5.3 A, so it needs its own 230 V circuit with a matching plug (typically NEMA 6-15 or 6-20). If the room has only ordinary 115 V outlets, an electrician has to add one. Only 100% of the 10 certified units in this class are 230 V.

What are the dimensions of the LG LW1822IVSM, and will it fit my window?

26" W × 17.7" H × 30.7" D, 112 lb. It is narrower than 11% of its 9 competitors and lighter than 33% of them. The window must be wider than 26"; the side panels fill the remaining gap.

Can the LG LW1822IVSM also heat the room?

No, it only cools. If you also need heat, 0 certified units in this class can do both; see the list of air conditioners with heat.

Is the LG LW1822IVSM worth buying to replace an old air conditioner?

An old unit of the same size at 9 CEER would cost about $271 a year to run at 750 hours and 18.0¢/kWh; this one costs about $166, so it saves roughly $105 a year.

18,000 BTU window air conditioner

LG LW1822IVSM

Average efficiency for its size: a CEER of 14.7 ranks #5 of 10 18,000 BTU window air conditioners.

It cools a room of about 700-1000 sq ft, draws about 1224 watts and costs about $166 a year to run at typical U.S. use and prices.

CEER: 14.7 Combined efficiency, higher is better
Average · beats 55%
Cooling: 18,000 BTU/hFor about 700-1000 sq ft
Energy use: 918 kWh/yr37% less than the federal minimum
Unit size: 26" wide 17.7" high, 30.7" deep, 112 lb

A good fit if…

You want a certified 18,000 BTU window air conditioner at a typical efficiency level.

Think twice if…

You only have ordinary outlets - it needs a 230 V circuit and plug.
You plan to install it alone - at 112 lb it is a two-person job.
You also need heat - it cools only.

Calculate my running cost Check the size for my room

Details

Specifications18,000 BTU, 230 V

General
Brand	LG
Model number	LW1822IVSM
Type	Window
Design	Standard box
Heating	No, cooling only
Compressor	Variable speed (inverter)
Voltage	230 V (needs a 230 V outlet)
Refrigerant	R-32 (GWP 675)
Support bracket included	Yes
On the market since	August 28, 2023
Last certified	September 18, 2023
Performance
Cooling capacity	18,000 BTU/h
CEERCombined energy efficiency ratio, includes standby power	14.7
Yearly energy useENERGY STAR test: 750 hours	918 kWh
Better than federal minimum	37% less energy
ENERGY STAR Most Efficient	No
Size
Width × height × depth	26" W × 17.7" H × 30.7" D
Weight	112 lb

How it compares with 9 other 18,000 BTU window units#5 of 10

CEER (class median 14.7)14.7, no ties
Yearly cost vs. class median ($169)$3 less
Width 26" (class median 25.4")narrower than 11%
Weight 112 lb (class median 99 lb)lighter than 33%
Rank among 5 similar designs#4

Compared with the other ENERGY STAR certified 18,000 BTU window units. Yearly cost at 750 hours and 18.0¢/kWh.

Questions6

How many square feet does the LG LW1822IVSM cool?: At 18,000 BTU/h it suits a room of about 700 to 1000 sq ft with normal sun and two people, following the ENERGY STAR sizing guide. In a heavily shaded room that stretches to about 770-1100 sq ft; in a very sunny one it shrinks to 630-900 sq ft. A kitchen needs 4,000 BTU more.
How many watts and amps does the LG LW1822IVSM use?: About 1224 watts at full power (18,000 BTU/h divided by its CEER of 14.7), which is 5.3 amps at 230 V. That is 26 W less than the typical unit in its class (1250 W), or $3 a year cheaper to run at 18.0¢/kWh. Its inverter compressor slows down instead of cycling, so real use is usually lower. Its CEER beats 50% of the 10 units in the class.
What outlet does the LG LW1822IVSM need?: It is a 230 V unit that draws 5.3 A, so it needs its own 230 V circuit with a matching plug (typically NEMA 6-15 or 6-20). If the room has only ordinary 115 V outlets, an electrician has to add one. Only 100% of the 10 certified units in this class are 230 V.
What are the dimensions of the LG LW1822IVSM, and will it fit my window?: 26" W × 17.7" H × 30.7" D, 112 lb. It is narrower than 11% of its 9 competitors and lighter than 33% of them. The window must be wider than 26"; the side panels fill the remaining gap.
Can the LG LW1822IVSM also heat the room?: No, it only cools. If you also need heat, 0 certified units in this class can do both; see the list of air conditioners with heat.
Is the LG LW1822IVSM worth buying to replace an old air conditioner?: An old unit of the same size at 9 CEER would cost about $271 a year to run at 750 hours and 18.0¢/kWh; this one costs about $166, so it saves roughly $105 a year.

Running cost calculator

Pre-filled with this model. Pick your state and how many hours you run it, or see the yearly cost in every state.

1. The air conditioner LG LW1822IVSM

Cooling capacity BTU/hCEER efficiency, higher is better

2. How you use it

StateElectricity ¢ per kWhHours a day at full powerDays a year from your state's climate

Per year: $259
Per month of use: $47
Per day: $1.57
Per hour: 19.6¢
Power draw: 1224 W

Electricity used: 1,616 kWh a yearAn old 9 CEER unit of the same size would cost $422

Power draw is capacity divided by CEER, which already includes standby power. Inverter units often run below full power, so real use can be lower. Electricity prices: U.S. EIA residential averages (12 months to July 2026). Days a year start from your state's cooling degree days (NOAA 1991-2020 normals).

Closest alternatives

Units with a similar CEER in the same class, and what sets each one apart from the LG LW1822IVSM.

Model	CEER	Compared with this one
Kühl KCVM18B30B	14.6	0.1 CEER lower, 18 lb heavier, saddle design
Friedrich CCV18A30A	14.4	0.3 CEER lower, 4 lb heavier, U-shaped
TCL T18WQ2S	14.4	0.3 CEER lower, 0.6" narrower, 16 lb lighter, U-shaped
Friedrich KCVM18B30A	14.4	0.3 CEER lower, 18 lb heavier
Whirlpool WHAW-181IN	14.4	0.3 CEER lower, 4" wider, 6 lb lighter, U-shaped

See all 10 18,000 BTU window air conditioners, ranked

Source: ENERGY STAR Certified Room Air Conditioners (U.S. EPA), certification of September 18, 2023. How we use the data.