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Keystone Energy Star 8,000 BTU Window Mounted Inverter Air Conditioner with Supplemental Heat, Quiet High Efficiency Window AC Unit with Remote for Apartment, Medium Rooms up to 350-Sq. Ft.

  • Based on 164 reviews
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Availability: Only 2 left in stock, order soon!
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Arrives Saturday, May 30
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Size: 8000 BTU


Style: Heat/Cool


Features

  • Heat Pump Window Unit 115v: This window ac with heat has cooling power, supplemental heating power, and dehumidifies in rooms up to 350 square feet; Supplemental Heating mode is meant to be operated when temperatures outside are between 41 and 75 degrees; Mode is supplemental and NOT meant as primary heat source
  • Inverter Technology: Eliminates wasted operation in the ac heater combo window unit by controlling the motor speed to exactly the amount of power that is needed to keep the room at the desired temperature
  • Quieter Operation: The inverter technology not only makes the window air conditioner with heat more energy efficient, but allows it to operate 24% quieter on low and 6% quieter on high than regular room air conditioners
  • Easy to Install: The ac and heater window unit fits in windows 14.5-in. tall with a minimum of 24-in. wide and maximum 38.5-in. wide
  • Washable Filter: A clean filter alert notifies you to clean the unit's washable filter to ensure it keeps running efficiently

Description

With reliable air conditioning units, Keystone produces consistent cooling to keep you comfortable, even on the hottest days. This 8,000 BTU inverter window-mounted air conditioner can effectively cool rooms up to 350 square feet with dehumidification up to 1.1 pints per hour to remove moisture from the air. Perfect for medium-sized living spaces like apartments, bedrooms, living rooms, and much more. A 7,000 BTU heat pump is also included for those chilly days. Supplemental Heating mode is meant to be operated when temperatures outside are between 41 and 75 degrees. This mode is supplemental and NOT meant as a primary heat source. It features special Inverter technology to eliminate wasted operation in the air conditioner by controlling the motor speed to exactly the amount of power that is needed to keep the room at the desired temperature. In addition, the inverter technology also makes this unit 17% more energy efficient than standard window units. A remote is included so you can control your cooling from across the room. Money saving features include energy saver mode, sleep mode, and a programmable 24-hour timer. You'll know when it's time to easily remove and clean the mesh filter with the Check Filter alert. Keystone not only provides a 1-year warranty but ensures that you stay cool and comfortable at a cost-conscious price.

Brand: Keystone


Capacity: 1.1 Pints


Cooling Power: 8000 British Thermal Units


Special Feature: 17% more energy efficient than average window units, Dehumidifier, Fast Cooling, Filter Light Reminder, Heating And Cooling Function See more


Product Dimensions: 22.17"D x 19.41"W x 13.9"H


BEE Star Rating: Yes


Start year: 2023


Seasonal Energy Efficiency Ratio (SEER): 14.5


Color: Bright White


Voltage: 115 Volts


Product Dimensions: 22.17 x 19.41 x 13.9 inches


Item Weight: 56 pounds


Manufacturer: Keystone


Item model number: KSTAW08INV-HC


Form Factor: Window


Number of pieces: 3


Warranty Description: 1 year limited


Batteries required: Yes


Included Components: Manual, Warranty, Remote, Batteries, Air Conditioner, Window Kit


Capacity: 1.1 Pints


Floor Area: 350 Square Feet


Voltage: 115 Volts


Noise Level: 54 Decibels


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Saturday, May 30

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


  • Good air conditioner
Size: 24000 BTU Style: Cool Only 230V
As for the unit it works great. It’s been in use since July of this year. It does a great job cooling a good size room. But for the packaging it did come damaged, luckily it didn’t affect anything important.
Reviewed in the United States on November 26, 2025 by DADE DADE

  • Dehumidifier and Cooling
Size: 8000 BTU Style: Cool Only
We live in the mountains where it is MOIST. Have you cooled moist air before? If you have, you understand why this is not so fun. This sucks the moisture right out. But not uncomfortably so. I can’t speak to how it would feel in dry environments. Noise is usually pretty quiet, we’ve been using it for about a month now. It only seems to get a little loud once in a while when it’s exceptionally hot. And by loud I mean, we hear it at all. We have it adjacent to the crib and it doesn’t seem to wake the baby. What’s nice is it pushes air up instead of straight out, which seems to make for more efficient cooling (cool air falling, creating a decent circulation.) It fit just fine in the window, but getting to to seal without outing nails in the wall was tricky. If the unit is ripped forward I got the room, that moisture it pull will come out that way. So make sure it is angled down and out of the house. It looks nice and blends into the room, very modern design. Cools quickly too despite being more energy efficient type. Can’t complain!!! ... show more
Reviewed in the United States on July 14, 2024 by Kevin P. Kevin P.

  • DOES NOT WORK IN THE WINTER! What's the point?!
Size: 8000 BTU Style: Heat/Cool
I bought this early November for a shed. We're putting in flooring and insulation, and this was going to be the perfect answer to keeping it both cool in the summer and warm in the winter. Except nowhere on this Amazon page does it tell you the heater part doesn't work if the outside temperature is below a certain temp. What good is it at that point? It wouldn't even turn on OVER that temp, so even more worthless. Save your money and get a different solution. I feel INCREDIBLY mislead to get a 50+ pound product I have to return because the seller didn't give me a critical piece of information in the listing. This has been an absolute PITA, and ended up costing me money. Very frustrated. ... show more
Reviewed in the United States on November 28, 2023 by Rebekah

  • Pretty solid unit
Size: 8000 BTU Style: Heat/Cool
Operates quietly. Isn’t too heavy. The controls are easy to use. It needs to be more prominent in the ad that the heating will not work below 41* f. Which tells me it’s a heat pump with no emergency heat bank. Fortunately that isn’t a huge issue for me but it might be for others who are expecting more from this moderately priced unit 👍. A/c works great a+. Heating aspect gets a B- design, use, appearance and ease of install A+ ... show more
Reviewed in the United States on November 11, 2023 by John B. Cornwell III

  • Chilly how I like it
Size: 12000 BTU Style: Cool Only
It works well, it’s smart, is geo and wifi enabled, you can have it on a schedule. I love it. I have to say though it never feels like a true 61 degrees. It feels like 70 degrees which is fine. It’s just not ice cold. When I drive home within a certain range or time, it turns on and my place is cool for me when I get home. ... show more
Reviewed in the United States on June 16, 2025 by Louie Louie

  • Cools larger room quickly.
Size: 24000 BTU Style: Cool Only 230V
Cools larger rooms very quickly. Easy to use. Directions very clear as to how to install. Remote easy to use and understand. Quality seems pretty sound. Not the quietest AC I have ever used, but for its BTU not that bad either. Easy to install.
Reviewed in the United States on July 26, 2025 by JacQue

  • One out of Four
Size: 8000 BTU Style: Cool Only
This is the fourth one I bought, guess I was lucky. I love the low noise and ease of installation. This one was making a noise when I plugged it in, then it quit cooling and throwed error code. Looked it up and it said low on refrigerant.
Reviewed in the United States on May 21, 2025 by Cy

  • Love it very cold
Size: 24000 BTU Style: Cool Only 230V
Works great well worth the price can't turn it to 60 you can't stand the cold and it's cooling my living room dining room and kitchen and bedroom I live in a old house with huge rooms couldn't ask for anything more
Reviewed in the United States on August 3, 2025 by Shannon

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