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LG

LG 18,000 BTU Smart Window Air Conditioner, 230/208V, Cools Room up to 1000 Sq. Ft. for Bedrooms, Living Room, Apartments, with Remote, 3 Fan Speeds, 24-Hour Timer, White

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Availability: In Stock.
Fulfilled by Buildcom
Arrives Oct 11 – Oct 14
Order within 17 hours and 40 minutes
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Size: 18000 BTU


Style: Wifi & High Efficiency


Color: White


Features

  • Window Air Conditioner with Low Noise Performance: LG window air conditioners operate at sound levels as low as 52dB (in low mode) eliminating unnecessary noise; Get a good night's sleep and work without distraction with this air conditioner window unit
  • Multiple Fan Speeds: 3 cooling and fan speeds with Auto Cool allow you to customize your cooling; Adjust the ac window unit air flow to suit your needs
  • AC Window Unit with Timer: Create your own cooling schedule to save on energy costs with the 24 hour on/off timer
  • Cools Rooms up to 1,000 Square Feet: LW1821ERSM is ideal for cooling large rooms (25' X 40'); With the 1,000 square feet cooling coverage, keep your bedroom, office, or any other large space comfortably cool with this window unit ac

Description

Experience the ultimate in cooling convenience and efficiency with the LG window air conditioner. This smart air conditioner allows you to cool your home from anywhere using LG ThinQ technology, enabling control with your smartphone or through voice commands with Amazon Alexa or Google Assistant. Designed for medium rooms up to 1000 sq. ft., this quiet window AC unit delivers powerful cooling while helping to save on energy consumption. With three cooling and fan speeds, as well as a 24-hour timer, you can easily create a personalized cooling schedule that suits your needs. The 4-way air deflection feature ensures that the airflow can be directed precisely where it's needed, providing optimal comfort whether you're cooling, dehumidifying, or simply circulating the air. In the event of a power outage, the auto restart feature will automatically resume operation once power is restored, eliminating the hassle of manually turning on the unit. The included remote control allows for convenient operation from anywhere in the room, while the easy window installation kit simplifies setup. The slide-out washable filter promotes clean and healthy air circulation, and the check filter alert reminds you when it's time to clean or replace the filter for efficient performance.

Brand: LG


Cooling Power: 18000 British Thermal Units


Special Feature: Window Air Conditioner


Product Dimensions: 25.98"D x 28.11"W x 17.68"H


BEE Star Rating: No


Start year: 2021


Seasonal Energy Efficiency Ratio (SEER): 11.9


Color: White


Voltage: 230 Volts


Refrigerant: R 410A


Product Dimensions: 25.98 x 28.11 x 17.68 inches


Item Weight: 130 pounds


Manufacturer: LG Electronics


Item model number: LW1821ERSM


Form Factor: Window


Warranty Description: 1, Year Limited Warranty


Batteries required: No


Included Components: LW1821ERSM Window Air Conditioner, Window Installation kit, Remote control


Floor Area: 1000 Square Feet


Voltage: 230 Volts


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Oct 11 – Oct 14

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews

    • Perfect Cooling for a Small Office!
Size: 5000 BTU Style: Remote Color: Bright White
This LG 5,000 BTU window air conditioner is exactly what I needed for my office space (about 10x15 feet). It cools the room quickly and quietly, and the remote makes it super convenient to adjust settings without getting up. Installation was straightforward, and it fits securely in the window. It’s efficient, reliable, and keeps the space comfortable even on hot days. Highly recommend for small rooms or office setups! ... show more
Reviewed in the United States on August 17, 2025 by Ann Guardino
    • LG window ac 12k btu.
Size: 12000 BTU Style: Cool Only 115V Color: White
I am a little over a week in to this unit and can't find a single negative thing to say about it Installation was not too difficult because I had a friend help me do the install as it is kind of heavy and bulky, plus I wanted it installed CORRECTLY. I can't get over how quiet this unit is and how well it cooks my retail bait and tackle store. When though it's a smaller, "mom and pop" type place, it cooled the whole shop off to a very comfortable 68 degrees F in about half an hour. The unit completely got rid of 95+% humidity inside the store within 45 minutes and I am very happy with it's ability to keep the place cool, dry, and shit if when it reaches the temp the unit is set at. Overall, I give it 5 stars. I took into account the cost, ease of install, and functionality. It checks every box I listed before making a decision on purchase. Other reviews were very good so I decided to retire my barely functioning 6k but Haier unit and I could not be happier. I will add to this review in a month and then again in, most likely, October. Which is the end of my season and need for the unit because here in NY. The weather tends to be more comfortable and the unit will not be needed. I will add, if you are on the fence between a unit that has less btu's and this one, go with the higher btu unit. It is definitely worth it and for a free extra dollars, you will not be disappointed! Any questions just ask. ... show more
Reviewed in the United States on June 19, 2025 by Susan Surdow
    • Maybe I got a lemon? Will you get one too?
Size: 12000 BTU Style: Electronic & High Efficiency Color: White
A big hello to all my fellow cool people, or should I say, wanting to be cool? I live in an older house with no central air. Having at least one room that is able to be kept very cold for my huskies is quite important. In the summer they can sleep downstairs in the living room with fans on, the circulation in the house from the fan in the attic keeps it decently cool there. I love to give them COLD temperatures all year round. I, too, enjoy being cool on hotter summer days. I have submitted this item for return the first day I just got it and had family help me install it. Why? This unit is a couple of thousand BTUs higher than a mobile Vremi unit I own [which has lost its efficiency after 1.5-2 years]. It does not even perform as good as that one. That was a shocker. Cold air does not emit from this AC. This was ensuring I had everything set proper. Proper mode, proper vent setting [it can be on or off of course if you want to circulate outside air], and the fact that this cools rooms up to 550 sq ft left me very surprised to see it not work, since the room I put it in is less than 300 sq ft. If I had a king or queen bed in this room, it would be the majority of the room. The air was mildly cool at best coming from the AC. I even took my shirt off and let the air from the AC hit my torso. Not cold. [60 degree setting] I decided to run some experiments. I ran the AC [again, proper mode and settings] from 60 degrees to 80 degrees in variance. There was no change in the temperature of the air coming from the LG AC. There was never a shift in the fan or power of the AC either, unless I changed the fan setting. Only F1 seemed to initiate any kind of substantial shift. By that all I mean is an audible noise. I was in the room with the AC for a couple of hours. It was not cooling the room. [Proper settings, room secure, etc.] I had no choice other than to return it. I even got a prompt saying they would give a partial refund. I would not even keep this AC if they fully refunded me, as it is NOT working. I don't expect an AC to cool a room in 10 seconds flat during warmer summer days, but it needs to move the needle. This has some bad reviews and some good reviews, you're taking your chance if you want to buy it. Maybe you will have better luck. As far as any positives I can say since I don't want to appear to be unreasonable here we go: The remote control works perfectly fine. I like the cosmetics of the AC and the control panel. As far as the noise level, it wasn't unreasonable. I left energy efficiency at 3 stars because I cannot speak to that after only having the AC for a day. If the AC had just worked, it would have been great. I was going to even try to return it for a like item to try another, but Amazon's auto-return instructions told me I could not do that. Anyway, hopefully my review could help sway you one way or another on a potential purchase. Be prepared to have to return it. Edit- Bought a 14,000 BTU GE model AC from a nearby store. Works like a charm. Air was super cool and the low setting was on par with this LG model high setting. Again, I probably got a faulty model, but that’s my experience. ... show more
Reviewed in the United States on June 20, 2022 by Tyler
    • Measuring properly matters
Size: 14000 Style: Wifi & High Efficiency Color: Bright White
My husband and I love this ac by LG. Pay very close attention to the dimensions. They are very precise. Installation was a bit more than we expected. But, that isn’t anyone’s fault but our own. We ended up having to remove the storm window to get it to fit. Again, not any fault by LG. My husband didn’t read the directions first. Once he read them he took the cover off the front and back. I helped him slide it in from the inside. He leveled it, out the coverings back on, and voila! It fit like a glove. We upgraded the btu from 12000 to 14000. The difference is amazing. This unit cools our entire first floor. Which is our enclosed front porch, living room, dining room, kitchen, bedroom and bathroom. I’d estimate the square footage to be around 900 square foot. Give or take a few. We especially love the quietness of this unit. The directional vents are large and puts out plenty of cold air. We have the WiFi feature, but don’t anticipate using it. But, who knows? In summary, we love this unit. Yes, a bit dicey getting it in the window. But, that was our fault. It looks great. Recommend this unit. Plus, Amazon delivered it 2 days sooner than expected. Which was so appreciated as our old ac stopped working. Thank you Amazon! ... show more
Reviewed in the United States on August 17, 2025 by Linda Johnson
    • Good unit lasting a surprisingly long time in harsh conditions. Fan can stop when on low
Size: 5000 BTU Style: Mechanical & Standard Color: White
Made it not quite 3 years in very harsh conditions. I use it in my small shed, activated by humidity. So, the air is always full of gasoline and chemicals in there. It keep humidity down to nothing rusts or rots in my shed. I gave it 4 stars because the fan stops sometimes if the outside part gets stuff in it when on low speed. That's a little annoying. But, it is not dehumidifying well anymore and the temperature is rising on the output, so the refrigerant is leaking out. It was so inexpensive and a good unit. I will buy it again. It's nice and small to fit my shed window. I like that the controls are basic and simple so that I can use my dehumidistat with it. ... show more
Reviewed in the United States on September 13, 2025 by D. Hoover

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