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Keystone Energy Star 12,000 BTU Window Mounted Inverter Air Conditioner with Supplemental Heat, Quiet High Efficiency Window AC Unit with Remote for Apartment, Medium-Large Rooms up to 550-Sq.Ft.

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Availability: In Stock.
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Arrives Monday, May 25
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Size: 12000 BTU


Style: Heat/Cool


Features

  • Cooling and Supplemental Heating Power: This air conditioner has 12,000 BTUs of cooling power, 10,000 BTUs of supplemental heating power, and dehumidifies the air up to 1.73 pints per hour in rooms up to 550 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 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 unit more energy efficient, but allows it to operate 22% quieter on low and 5% quieter on high than regular window units
  • Easy to Install: This AC 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 conveniently 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 12,000 BTU inverter window-mounted air conditioner can effectively cool rooms up to 550 square feet with dehumidification up to 1.73 pints per hour to remove moisture from the air. Perfect for medium-sized living spaces like apartments, bedrooms, living rooms, and much more. The 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 18% 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 provides a dependable 1-year warranty.

Brand: Keystone


Capacity: 1.73 Pints


Cooling Power: 12000 British Thermal Units


Special Feature: 18% 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


Start year: 2023


Seasonal Energy Efficiency Ratio (SEER): 13.3


Color: Bright White


Voltage: 115 Volts


Noise Level: 58 Decibels


Cooling Power: 12000 British Thermal Units


Additional Features: 18% more energy efficient than average window units, Dehumidifier, Fast Cooling, Filter Light Reminder, Heating And Cooling Function


Color: Bright White


Noise: 58 Decibels


Refrigerant: R-32


Filter Type: Washable


Core Material: Aluminium Alloy


Inverter Type: Has Inverter


Installation Type: Window


Compressor Type: Inverter


Is Outdoor Unit Required: No


Air Conditioner Application: Residential Indoor


Voltage: 115 Volts


Power Source: Corded Electric


Wattage: 1214 watts


Is Product Cordless: No


Is Electric: Yes


Seasonal Energy Efficiency Ratio (SEER): 13.3


Efficiency: 13.3 (SEER value), High


Annual Energy Consumption: 1214 Watts


Capacity: 1.73 Pints


Floor Area: 550 Square Feet


Room Type: Bedroom, Living Room


Form Factor: Window Air Conditioner


Brand Name: Keystone


Start Year: 2023


Model Name: Keystone Energy Star 12,000 BTU Window Mounted Inverter Air Conditioner with Supplemental Heat


Model Number: KSTAW12INV-HC


UPC: 840148724396


Manufacturer: Keystone


Item Type Name: Keystone Energy Star 12,000 BTU Window Mounted Inverter Air Conditioner with Supplemental Heat, Quiet High Efficiency Window AC Unit with Remote for Apartment, Medium-Large Rooms up to 550-Sq.Ft.


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


Warranty Description: 1 year limited


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


Item Weight: 58 Pounds


Window Opening Maximum Width: 38.5 Inches


Window Opening Minimum Height: 14.5 Inches


Window Opening Minimum Width: 24 Inches


Window Opening Maximum Height: 14.5 Inches


Control Method: Remote, Touch


Controller Type: Remote Control


BEE Star Rating: 4 Star


Warranty Type: Limited


Number of Heating Elements: 1


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Monday, May 25

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


  • Seems well made and is very effective in mild weather
Size: 12000 BTU Style: Heat/Cool
I've ysed this unit for about about a month in the middle of Missouri. For days above 40, this unit will crank out a ton of hot or cold air as appropriate (Missouri has insane weather). When holding your hand to the vent, the heat doesn't seem too hot but it moves such an amount of air through the vent that it can effectively heat the room in just a few minutes. That being said, I really wish it would heat below 40°F. It seems the addition of a defrost feature would multiply the unit's usefululness several fold. I have a Toshiba window unit that seems well made, but this unit is in another class entirely. Everything is thick and heavy; it feels like a quality product. ... show more
Reviewed in the United States on November 12, 2023 by Cazey

  • Works better than expected
Size: 12000 BTU Style: Heat/Cool
Bought for newly remolded detached 2 car garage. It kept the temp very comfortable last summer here in southeast VA. Electric bill did not go up very much. Maybe an extra 10 a month. Fit like a glove in the window. This past winter kept the temps at 60 even on days when the outside temp was in the 30’s. I recommend this unit. Especially since it’s 110v. Didn’t need to run a 220v line through newly finished drywall. ... show more
Reviewed in the United States on March 4, 2024 by tourglide

  • Worst money ever spent.
Size: 12000 BTU Style: Heat/Cool
After 10months of use it stopped working. Reached out to the manufactor and they stated I did not buy a new unit through Amazon(it was brand new) AC is no longer cooling but 50% of the time and it's the middle of August 110° last week. Amazon customer service is trying to help in the best way possible. We will see how it turns out ... show more
Reviewed in the United States on August 20, 2024 by THOMAS MANNION

  • Window unit
Size: 12000 BTU Style: Heat/Cool
Did not know what to expect but air conditioner works awesome ! Really cold I love it and would highly recommend it to anyone
Reviewed in the United States on August 30, 2023 by Wendy Leteff

  • Heat does not work when temperature is below 42 degrees
Size: 12000 BTU Style: Heat/Cool
The heat will not work if the temperature is below 42 degree’s!! Disappointing!! The a/c works as it should.
Reviewed in the United States on August 13, 2025 by Amazon Customer

  • It works
Size: 12000 BTU Style: Heat/Cool
Great product! It’s enough to cool my 900 square foot florida home in the month of august to a comfortable 73f Working out better then expected
Reviewed in the United States on September 9, 2023 by Amazon Customer

  • Very interesting unit
Size: 12000 BTU Style: Heat/Cool
This is the only window heat pump unit I found at a reasonable price. It is variable speed, using R-32, and is pretty efficient. Runs quiet, even on high. Blows good heat, 114-120F air exhaust at a 68F air inlet temp and 43F outside temp. Automatically adjusts compressor speed to maintain temp in range based on fan speed. Good air flow, but not evenly distributed over louver (this is normal). Overall I am impressed. Why the manufacturer did not add a defrost circuit to run it below freezing is a mystery. They were 90% of the way to having a really useful product and then stopped. R32 can generate heat below 0F outside temps with no problem. This would be a great unit for mild winters. For the northern half of the US, a split system is required. Again, the manufacturer really screwed up bad by not adding the defrost circuit. They could have dramatically expanded their potential market. Dumb, just plain dumb. ... show more
Reviewed in the United States on February 25, 2024 by John Public

  • Gr8 product
Size: 12000 BTU Style: Heat/Cool
Wonderful addition to my workshop
Reviewed in the United States on January 28, 2025 by MAS

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