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11,500 BTU Thru-the-Wall Air Conditioner with remote

  • LT121CNR

Key Features

  • Universal Fit for Sleeve
  • Gold Fin Anti-Corrosion
  • 3 cooling and fan speeds with Auto Cool
  • 4-way air direction
EER 8.8
Dehumid. (Pts/Hr) 3.8
Dry Air Flow (CFM) 290
dBA Level (Indoor / Outdoor) 52 / 61
BTU Performance Cooling 11,500
Net Weight (lbs.) 80
Shipping Weight (lbs.) 87
Carton Height (inch) 17 13/32
Carton Width (inch) 27 23/32
Carton Depth (inch) 22 13/32
Dimension Height (inch) 14 13/32
Dimension Width (inch) 24
Dimension Depth (inch) 20 3/32
Thermostat Control Thermistor
Air Deflection 4-Way
Remote Control Yes
Energy Saver Function Yes
Programmable Timer 24Hr, On/Off
Fan Speed: Cooling (Heating) 3
Compressor Rotary
Indoor Fan Type Turbo
Type Air Discharge Top
Outdoor Vent / Exhaust Yes
Chassis Type XB
Auto Restart Yes
Fan Only 3
Real Grille Yes
Voltage / 60 Hz 115
Watts (Cooling) 1,310
Rated Amps (Cooling) 12.0
Warranty 1 Year Parts and Labor(Limited In-Home Service)

What People Are Saying

Rated 1 out of 5 by from DO NOT BUY THIS UNIT I've had this AC for nearly 2 months, and it performs worse than the 40 year old AC removed. The old one worked - not good - but it worked. This one recycles over, and over and over all day long, and it never reaches the temperature that I've got it set at. I've got an "atomic clock" with temperature control, only 8 feet directly in front of it. I'm so disappointed in this unit. If it were possible, I'd have my contractor take it out, and I'd return it to the store. DO NOT BUY THIS UNIT
Date published: 2014-07-08
Rated 4 out of 5 by from Better than expected, but a bit difficult to insta This unit very well cools an area larger than specified. It may be a Home Depot issue, but I'm not sure I bought the proper wall sleeve and it was a bit difficult to install.
Date published: 2012-12-04
Rated 4 out of 5 by from powerful fan blower Although this AC is only rated at 11500 BTU it has a very strong fan that makes all the difference in a room. I have a small ranch home that has a large 410 SF room facing West that takes a beating from the hot summer sun in the afternoon. This AC fan blows cold air clear across the large room and makes staying inside bearable on a hot day.
Date published: 2012-06-20
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We're here to support you with our product.

View LT121CNR Product Support

Contact us for any purchasing inquiries.


Ask your questions. Share your answers.
Please first review the detailed product information and help guides in the Product Support section for this product prior to posting a question.

Fan speed not setting?

Anytime i turn on the AC it starts at fan speed 2 and can only be switched to 3 no matter how i set the fan speed to 1 it always reverts back to 2 regardless is their anything i can to turn it down to fan 1 i dont need it always at 2/3?
Asked by: Meech
It is the design of the FAN SPEED control to always advance the speed of the fan in the following progression: HIGH -> LOW -> MED -> HIGH. As such, if the fan is running in the HIGH speed, pressing the FAN SPEED button on the remote control should drop the fan to its LOWEST speed. If this is not the case, then the unit may require service. To make service arrangements, you may either contact our Customer Interactive Center at 800-243-0000, or you can check our Repair Provider Lookup on our website, at
Answered by: NeilE
Date published: 2013-06-05

outside cover?

We recently had an LT121CNR installed and there is no cover on the outside of the unit, which is exposed to the elements. Should there be a metal cover or shield on the fins and other components?
Asked by: Michael
Yes, you need a through the wall sleeve, but good like finding it. I couldn't find which one was the proper one either on LG's or Home Depot's websites.
Answered by: Rick69
Date published: 2013-03-05

Wall electrical outlet for LG LT121CNR AC?

What type of wall power outlet is required? Standard 15 amp? 20 amp?
Asked by: bobm85301
It only draws 10 amps, so a 15 amp wall socket is most acceptable.
Answered by: Rick69
Date published: 2013-03-05

Is a through the wall sleeve necessary?

Can the unit be removed from the outer casing, the casing be mounted and then re-install the unit in the casing?
Asked by: Spinax
Yes, you would need a sleeve for it. LG's universal Thru the Wall sleeve will fit the standard size for wall openings.
Answered by: Nadine
Date published: 2012-11-06

where is condensation plug on bottom of lt 121cnr

Asked by: Anonymous
This unit has not been designed with a “condensation plug”. It is designed so that the majority of the condensation is thrown onto the condenser coils, using what we call a “Slinger Fan”, in a manner which increases the efficiency of the operation of the unit. If too much moisture is drawn, the water will naturally spill out of the back of the unit.
Answered by: Neil
Date published: 2011-07-01

what is quietest LG thru-wall unit in 10,000 BTU range and what are the decibels?

Asked by: Andrew
Thank you for your question. You should find all of the measurements and specifications for your unit at If the information is not there, please feel free to contact one of product specialists at 1-800-243-0000 or via live chat @
Answered by: Stan
Date published: 2012-03-24

wall sleave

what is the wall sleave that works with your model LT121CNR air conditioner
Asked by: mikeydoin
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