Product Overview
The Keystone 12,000 BTU Window Mounted Inverter Air Conditioner is designed to provide consistent cooling and dehumidification for medium-sized living spaces. Its advanced Inverter technology ensures quiet and energy-efficient operation, adapting the motor speed to maintain your desired temperature precisely.

Image: Front view of the Keystone 12,000 BTU Window Mounted Inverter Air Conditioner.
Key Features:
- Cooling Power: 12,000 BTUs, suitable for rooms up to 550 square feet.
- Dehumidification: Removes up to 1.85 pints of moisture per hour.
- Inverter Technology: Provides quiet, high-efficiency operation and 20% more energy efficiency than standard units.
- FlashCool Function: Engages maximum cooling and high fan speed for rapid room cooling.
- Washable Filter: Features a 'Check Filter' alert for easy maintenance.
- Convenience Features: Includes Energy Saver mode, Sleep mode, and a programmable 24-hour timer.
- Remote Control: Allows convenient operation from across the room.
Setup and Installation
Proper installation is crucial for optimal performance and safety. This unit is designed for window mounting and includes a window installation kit.
Dimensions and Compatibility:
- Product Dimensions: 18.98"D x 21.69"W x 14.65"H
- Item Weight: 50.9 pounds
- Compatible Window Width: 23 inches to 36 inches

Image: Diagram showing the dimensions of the Keystone 12,000 BTU Window Mounted Inverter Air Conditioner.
Electrical Requirements:
- Plug Type: LCDI 5-15P Plug
- Voltage: Standard 115-Volt/25Amp
- Cable Length: 6.5 ft. LCDI

Image: Illustration of the AC unit's plug type and cable length.
For detailed installation steps, please refer to the included 'User Guide (PDF)' document.
Operating Instructions
Your Keystone air conditioner offers various modes and settings for personalized comfort. The control panel is located on the front of the unit, and a remote control is also provided.

Image: Close-up view of the control panel on the Keystone AC unit.
Available Modes:
- Cool Mode: Provides powerful cooling for your room.
- Dry Mode: Dehumidifies the air, reducing moisture.
- Fan Mode: Circulates air without cooling.
- Auto Mode: Automatically selects the appropriate mode (Cool, Dry, or Fan) based on the room temperature.
- Sleep Mode: Adjusts temperature and fan speed for comfortable sleep and energy savings.
- Energy Saver Mode: Optimizes operation to reduce energy consumption.
Additional Functions:
- FlashCool: Activates maximum cooling and high fan speed for quick temperature reduction.
- 24-Hour Timer: Program the unit to turn on or off at specific times.
- Fan Speeds: Choose from 3 fan speeds (High, Low, Quiet) to suit your preference.
- Remote Control: Use the included remote for convenient adjustment of settings.

Image: A hand holding the remote control for the air conditioner, highlighting the 'Cooling in a Flash' feature.
Maintenance
Regular maintenance ensures the longevity and efficiency of your air conditioner.
Cleaning the Washable Filter:
The unit is equipped with a washable mesh filter. A 'Check Filter' alert will illuminate on the control panel when it's time to clean the filter. This typically occurs after approximately 250 hours of operation.
- Carefully remove the front panel and slide out the mesh filter.
- Wash the filter with warm, soapy water.
- Rinse thoroughly and allow it to air dry completely before reinserting.

Image: A hand washing the removable mesh filter under running water.
Do not operate the unit without the filter in place.
Troubleshooting
This section provides solutions to common issues you might encounter with your air conditioner. For more complex problems, please refer to the full user guide or contact customer support.
Common Issues and Solutions:
- Unit does not turn on: Check if the power cord is securely plugged into a working outlet. Ensure the circuit breaker has not tripped.
- Unit is not cooling effectively: Verify that the air filter is clean. Check for any obstructions to airflow around the unit. Ensure windows and doors are closed in the room being cooled.
- Unusual noises: Minor noises during operation are normal. If you hear loud or persistent unusual noises, consult the full user manual.
- Water dripping from unit: Small amounts of condensation are normal. If excessive water is dripping, ensure the unit is properly tilted for drainage.
Specifications
| Feature | Detail |
|---|---|
| Brand | Keystone |
| Model Number | KSTAW121WA |
| Cooling Power | 12000 British Thermal Units |
| Floor Area Coverage | 550 Square Feet |
| Voltage | 115 Volts |
| Noise Level | 53 dB |
| Seasonal Energy Efficiency Ratio (SEER) | 15.0 |
| Product Dimensions | 18.98 x 21.69 x 14.65 inches |
| Item Weight | 50.9 pounds |
| Color | Bright White |
| Included Components | Air Conditioner, Window Kit, Manual, Warranty, Remote, Batteries |
Warranty and Support
Warranty Information:
Your Keystone 12,000 BTU Window Mounted Inverter Air Conditioner comes with a 1-year limited warranty from the date of purchase. This warranty covers defects in materials and workmanship under normal use.
Please retain your proof of purchase for warranty claims.
Customer Support:
For technical assistance, troubleshooting beyond this manual, or warranty inquiries, please contact Keystone customer support. Refer to the contact information provided in your full user guide or visit the official Keystone website.
You can also find additional resources and FAQs on the Keystone Store on Amazon.





