1. Introduction
Thank you for choosing the Hisense AH121CK Split Air Conditioner. This manual provides essential information for the safe and efficient operation, installation, and maintenance of your new air conditioning unit. Please read this manual thoroughly before using the appliance and retain it for future reference.
This unit is designed to provide comfortable cooling for your indoor environment with features like Smart Mode, Super Cool, and easy maintenance.

Image: Hisense CK Series Split Air Conditioner indoor unit.
2. Safety Information
Always follow basic safety precautions when using electrical appliances to reduce the risk of fire, electric shock, or injury.
- Professional Installation: Installation and maintenance should be performed by qualified service personnel. Improper installation can lead to electric shock, fire, or water leakage.
- Power Supply: Ensure the power supply matches the specifications of the unit (115V). Do not use extension cords or multi-outlet adapters.
- Grounding: The appliance must be properly grounded to prevent electric shock.
- Children and Pets: Keep children and pets away from the unit during operation and maintenance.
- Cleaning: Disconnect power before cleaning. Do not use water directly on the unit.
- Obstructions: Do not block the air inlet or outlet of the indoor or outdoor unit.
- Refrigerant: This unit uses R-410A refrigerant. Do not attempt to service the refrigerant system yourself.
3. Product Features
The Hisense AH121CK Air Conditioner is equipped with several features designed for comfort and convenience:
- Smart Function: Automatically adjusts to the ambient temperature for optimal comfort.
- Super Cool: Rapidly cools the room by operating at maximum power and airflow.
- I Feel: Provides precise, comfortable, and uniform temperature control based on the remote control's sensor.
- Regulator: Allows you to turn off the light from the front panel.
- Easy Clean: The filter can be easily removed for cleaning with water.
- Refrigerant Leakage Detection: The evaporator automatically stops operation and displays an error code if a refrigerant leak is detected.
- Automatic Restart: The unit will resume operation immediately without manual intervention after a power outage.
- 24 Hours Timer: Program the unit to turn on or off at specific times.
- Auto Defrost: Prevents ice buildup on the outdoor unit.
- Cold Air Protection: Prevents cold air from blowing directly when the unit starts in heating mode (if applicable).
- Sleep Function: Adjusts temperature and fan speed for comfortable sleep.
4. Setup and Installation
The Hisense AH121CK is a split-type air conditioner, requiring both an indoor and an outdoor unit. Professional installation is highly recommended to ensure proper function and safety.
4.1 Unpacking
Carefully unpack all components. Verify that all items listed in the packing list are present and undamaged. Keep packaging materials for potential future transport or service.
4.2 Choosing an Installation Location
- Indoor Unit: Select a location that allows for even air distribution, away from direct sunlight or heat sources. Ensure there is enough space around the unit for maintenance and airflow.
- Outdoor Unit: Choose a location with good ventilation, away from obstacles that might block airflow. Ensure it is on a stable, level surface and away from noise-sensitive areas.
4.3 Electrical Connection
The unit requires a 115V electrical supply. All electrical work must comply with local codes and regulations and be performed by a licensed electrician. Ensure a dedicated circuit is used for the air conditioner.
5. Operating Instructions
Your Hisense AH121CK Air Conditioner is controlled via the included remote control. Familiarize yourself with the remote's buttons and functions.
5.1 Basic Operation
- Power On/Off: Press the ON/OFF button to start or stop the unit.
- Mode Selection: Press the MODE button to cycle through available modes (e.g., Cool, Dry, Fan, Smart).
- Temperature Adjustment: Use the TEMP UP/DOWN buttons to set your desired temperature.
- Fan Speed: Press the FAN button to adjust the fan speed (Auto, Low, Medium, High).
5.2 Special Functions
- Smart Mode: Press the SMART button. The unit will automatically adjust settings based on room conditions.
- Super Cool: Activate by pressing the SUPER button for rapid cooling.
- I Feel: Press the I FEEL button. The remote control will act as a thermostat, sensing the temperature around you for more accurate control.
- Regulator (Light Control): Press the REGULATOR button to turn off the display light on the indoor unit, useful during sleep.
- Timer: Use the TIMER ON/OFF buttons to set a scheduled operation time. Refer to the remote control manual for detailed timer settings.
- Sleep Function: Press the SLEEP button to activate a mode that gradually adjusts the temperature and fan speed for optimal sleeping conditions.

Image: Smart Mode functionality diagram.

Image: Super Cool feature in action.

Image: I Feel function for personalized comfort.

Image: Regulator function for display light control.
6. Maintenance
Regular maintenance ensures the longevity and efficiency of your air conditioner. Always disconnect power before performing any maintenance.
6.1 Air Filter Cleaning
The air filter should be cleaned every two weeks or more frequently depending on usage and air quality.
- Open the front panel of the indoor unit.
- Remove the air filter by gently pulling it out.
- Clean the filter with a vacuum cleaner or wash it with lukewarm water (below 40°C).
- Allow the filter to dry completely in a shaded area before reinstalling.
- Reinstall the filter and close the front panel.

Image: Easy filter cleaning process.
6.2 General Cleaning
Wipe the indoor unit with a soft, dry cloth. For stubborn dirt, use a damp cloth with a mild detergent, then wipe dry. Do not use harsh chemicals or abrasive cleaners.
6.3 Seasonal Checks
- Before Season: Check for any obstructions around the outdoor unit. Ensure the drainage hose is clear.
- After Season: Clean the air filters and turn off the main power supply if the unit will not be used for an extended period.
7. Troubleshooting
Before contacting customer support, review the following common issues and solutions.
| Problem | Possible Cause | Solution |
|---|---|---|
| Unit does not start | No power, circuit breaker tripped, remote control batteries low. | Check power supply, reset breaker, replace remote batteries. |
| Insufficient cooling | Dirty air filter, blocked outdoor unit, wrong mode selected, room too large. | Clean filter, clear obstructions, select Cool mode, ensure unit capacity matches room size. |
| Unusual noises | Loose parts, foreign objects, normal operating sounds (e.g., refrigerant flow). | Check for loose parts, remove foreign objects. If persistent or loud, contact service. |
| Water leakage | Blocked drain hose, improper installation. | Check and clear drain hose. If issue persists, contact professional installer. |
| Error Code Displayed | System malfunction, refrigerant leakage. | Note the error code and refer to the detailed troubleshooting section in the full manual or contact service. For refrigerant leakage, the unit will stop automatically. |

Image: Refrigerant Leakage Detection system.

Image: Automatic Restart function after power interruption.
8. Specifications
| Specification | Value |
|---|---|
| Brand | Hisense |
| Model Name | AH121CK |
| Capacity | 1 Ton (12000 British Thermal Units) |
| Cooling Power | 12000 British Thermal Units |
| Voltage | 115 Volts |
| Wattage | 1440 Watts |
| Noise Level | 41 Decibels |
| Refrigerant | R-410A |
| Product Dimensions (DxWxH) | 25.5 x 79 x 20 centimeters |
| Item Weight | 7.5 Kilograms |
| Seasonal Energy Efficiency Ratio (SEER) | 11.5 |
| BEE Rating | 5 Star |
| Control Method | Remote Control |
| Installation Method | Split System |
| Outdoor Unit Required | Yes |
| Included Components | Remote Control, User Manual |
9. Warranty Information
The Hisense AH121CK Air Conditioner comes with a 1-year manufacturer's limited warranty. This warranty covers defects in materials and workmanship under normal use.
Please retain your proof of purchase for warranty claims. The warranty does not cover damage caused by improper installation, misuse, neglect, or unauthorized repairs. For full warranty terms and conditions, please refer to the warranty card included with your product or contact Hisense customer support.
10. Customer Support
If you have any questions, require assistance, or need to schedule service, please contact Hisense customer support:
Option 1: Phone Support
Call us at: 800 0088 880
Option 2: Online Support
Visit our official website: hisense.com.mx
Look for the 'Technical Support Chat' link in the bottom left corner of the website.
You can also call us at: +55 41 53 1200
Operating Hours:
- Monday - Friday: 9:00 am - 9:00 pm
- Saturday: 9:00 am - 3:00 pm