LG Dual Inverter Window Air Conditioner Review 2025

You don’t need me to tell you how hard it is to get anything done when you’re sweating away in a hot, humid room. A good window air conditioner is a must in these situations. Fortunately, most of the best air conditioners are Energy Star-certified to cool your room efficiently and economically.

One of the most efficient ACs available is the LG Dual Inverter Smart Window Air Conditioner, which uses state-of-the-art inverter technology to reduce energy costs while maintaining a comfortable room temperature.

I’ve tested dozens of ACs, and this one is one of the best I’ve used for large rooms; below are my experiences with it. (We recommend window ACs versus portable ACs for most people, but if you can’t fit a window unit in your home, check out our guide to the best portable air conditioners.)

Design and specs

The LG Window Air Conditioner (model number LW1517IVSM) has a 14,000 Btu capacity, which makes it ideal for rooms of about 800 square feet. It’s Energy Star-certified with a Department of Energy-tested combined energy efficiency ratio (CEER) of 14.7, which makes it one of the most efficient air conditioners available. The estimated yearly energy cost is $98.

The appliance has four modes of operation: standard (with four cooling speeds), energy saver, fan, and dehumidifying. It can be controlled via a smartphone app or the included remote control, though the app offers more functionality.

Setup process

Everything you need for installation is in the box, including window security brackets and insulating foam to provide a good seal. You’ll need to use your own tools for the installation. In particular, it’s helpful to have Phillips-head and flat-blade screwdrivers, an adjustable wrench, a level, a tape measure, a knife, scissors, and a pencil on hand.

Installation was a major pain and took me two hours. Here are the steps:

1. Unscrew the cabinet from the AC and remove the innards.
2. Put window sash seals on the window.
3. Attach the curtains to the unit, which involves awkwardly screwing in eight screws that don’t line up well.
4. Put the cabinet in the window.
5. Install the sill brackets.
6. Screw the cabinet into the sill brackets.
7. Stretch the curtains out to fit the window and screw them in.
8. Reinstall the AC’s innards.
9. Add the foam strip to the gap between the window panes.
10. Install the window security bracket.
11. Install the heatproof foam insulation over the curtains.
12. Attach the face, which involves holding it awkwardly and making sure the vent and cord stuck through and that and everything was lined up just right.

All this to say, I recommend having a friend help you with the heavy lifting.

After the grueling installation process, I was relieved to find that connecting the AC to the LG SmartThinQ app was seamless. It paired with my Android phone in no time, and I found the controls useful. You can set a schedule for when your AC runs, adjust the thermostat, and more.

Review of the LG Dual Inverter Air Conditioner

The LG LW1517IVSM is special because it uses dual inverter technology. Most air conditioners turn the compressor on or off to regulate the temperature. Inverter ACs feature variable-speed compressors that make micro-adjustments to the temperature. In the Department of Energy’s tests, this LG model achieved efficiency scores 25% better than the minimum Energy Star requirement.

But, how does it perform? When I test ACs, I set the heat in my house to 75 degrees and then blast the AC on high to see how much it reduces the heat in a 650-square-foot room. This LG model performed better than most other ACs I’ve tested, reducing the temp by 3.3 degrees in an hour.

Additionally, I used the LG LW1517IVSM all summer in our family room, where we spend most of our time. It kept us perfectly cool in the humid Michigan heat. We typically use “energy saver” mode, which takes full advantage of the inverter technology.

Another reason this model is excellent for our family room is its quiet operation. On high it registered 53 decibels, which is only slightly louder than your average home or quiet office. Plus, the transition between motor speeds was smooth. I never noticed any jolting or obnoxious sounds during my months of use.

Cons to consider

The biggest negative with the LG LW1517IVSM Window Air Conditioner is the installation process. And, in Michigan, it gets so cold you can’t leave window ACs in place during the winter. So, I have to relive the trauma of moving this 100+ pound behemoth each fall and spring.

I appreciate how the unit connects easily to my phone. Unfortunately, I couldn’t get it to connect to Amazon Alexa. I also wish I could sync the unit with my smart thermostat, but without Alexa as an intermediary, I wasn’t able to get that to work either.

You’ll also have to make sure your windows are large enough to accommodate this beast. Measure and make sure your windows are at least 27 inches wide but no more than 39 inches high. The window should also open to a height of 16 inches.

What are your alternatives?

I’ve tested dozens of ACs over the years, and despite the above cons, I still think the LG Dual Inverter Smart Window Air Conditioner is among the best. That said, it’s best if you have large windows, a large space to cool, and are willing to front-load the cost of an expensive air conditioner (though it will save you money in the long run).

In our guide to the best air conditioners, we ultimately chose the Frigidaire 14,000 BTU Inverter Window Room Air Conditioner (model FHWW145WE1) as the best AC for large rooms. It ultimately beat out the LG because it’s much easier to install and cools a bit better. It does run loud, however, and is more expensive to run than the LG.

If you’re looking for similar energy efficiency that works for smaller rooms and windows, the only unit I think comes close to achieving the energy efficiency of the LG model is the Midea MAW08HV1CWT

If you’re debating between a window AC vs a portable AC, we think window units are best for most people. However, if you don’t have windows to accommodate a traditional unit, check out our guide to the best portable air conditioners.

The bottom line

The LG LW1517IVSM is one of the best window air conditioners you can buy. It’s efficient, powerful, quiet, and easy to use.

If you have a room you want to cool that’s 800 square feet or so and that has a double-hung window at least 27 inches wide, the LG Dual Inverter AC is your best option for getting the job done. There are several ACs out there that cost less than this LG unit, but long-term, you will save on energy costs with this model.

If you don’t have $550 available to purchase an AC, many sellers offer plans with affordable monthly payments and 0% APR for those who qualify.