1. Product Overview
This manual provides instructions for the Ouyniei MJXFJ-150-A1 Composite Filter, designed for use with Xiaomi and Mijia Fresh Air System A1 models. This filter is equipped with RFID for proper system recognition and optimal performance, ensuring clean and fresh indoor air.
Key Features:
- Air Refreshment: Optimized air duct design significantly improves purification speed, quickly refreshing the air in your home.
- Deep Dust Removal: Multi-layer composite structure deeply filters to effectively remove airborne dust and protect indoor air quality.
- Odor Removal: Honeycomb activated carbon structure absorbs various odors, including cooking fumes and pet smells, maintaining a fresh and pleasant indoor environment.
- Long-term Purification: Advanced materials and processes ensure extended filter element operation, reducing replacement frequency.

Figure 1: Ouyniei MJXFJ-150-A1 Composite Filter
2. Safety Information
- Always disconnect the air purification system from power before attempting filter replacement.
- Do not attempt to wash or reuse the composite filter; it is designed for single-use replacement.
- Keep the filter out of reach of children and pets.
- Dispose of used filters according to local environmental regulations.
- Do not remove the RFID tag from the filter.
3. Package Contents
- 1 x Ouyniei MJXFJ-150-A1 Composite Filter with RFID
4. Installation Instructions
Follow these steps to correctly install your new composite filter:
- Power Off: Ensure your Xiaomi or Mijia Fresh Air System A1 is turned off and unplugged from the power outlet.
- Locate Filter Compartment: Refer to your air system's original user manual to locate and open the filter compartment. This is typically on the side or back of the unit.
- Remove Old Filter: Carefully remove the used filter. Note its orientation for correct installation of the new filter.
- Insert New Filter: Insert the new Ouyniei MJXFJ-150-A1 Composite Filter into the compartment. Ensure the RFID chip side is correctly oriented as per your air system's design. The filter should fit snugly without forcing.

Figure 2: Front and Back View of the Composite Filter

Figure 3: Side View of the Composite Filter

Figure 4: RFID Chip Location on the Filter
- Close Compartment: Securely close the filter compartment door.
- Power On: Plug in and power on your air system. The system should recognize the new filter via its RFID chip.
- Reset Filter Life Indicator: If your air system has a filter life indicator, reset it according to your system's instructions to ensure accurate tracking of the new filter's lifespan.
5. Operation
The Ouyniei MJXFJ-150-A1 Composite Filter operates automatically within your Xiaomi or Mijia Fresh Air System A1. Once installed, the air system will draw in air, passing it through the multi-layer filter media. This process effectively captures particulate matter, allergens, and absorbs various odors, continuously working to maintain a clean and fresh indoor air environment.
6. Maintenance and Replacement
For optimal air purification performance, regular filter replacement is essential. The filter life depends on local air quality, usage frequency, and the operating environment.
- Replacement Frequency: It is generally recommended to replace the filter every 6 to 12 months. Your air purification system's filter life monitor will provide a more precise indication of when replacement is needed.
- Cleaning: Do not attempt to clean the filter with water, vacuum cleaners, or any other methods. This can damage the delicate filter media and significantly reduce its effectiveness.
- Inspection: Periodically check the filter compartment for any dust buildup and clean the exterior surfaces of your air system with a soft, dry cloth.
7. Troubleshooting
- Air quality not improving after replacement:
Ensure the filter is installed correctly and the filter compartment is securely closed. Verify that the air system has recognized the new filter via its RFID chip. If the issue persists, consult your air system's original manual or contact customer support. - Air system not recognizing new filter:
Check that the filter is fully seated in its compartment and that the RFID chip is not obstructed or damaged. Try restarting the air system by unplugging it for a few minutes and then plugging it back in. If the problem continues, the filter may be faulty, or there might be an issue with the air system's sensor.
8. Product Specifications
| Brand | Ouyniei |
| Model | MJXFJ-150-A1 Composite Filter |
| Compatibility | Xiaomi Fresh Air System A1, Mijia Fresh Air System A1 |
| Dimensions (L x W x H) | 258mm x 258mm x 67mm (Approx. 10.16" x 10.16" x 2.64") |
| Type | Air Purifier Part (Composite Filter) |
| Special Features | RFID Chip for system recognition |

Figure 5: Filter Dimensions
9. Warranty and Support
For warranty information or technical support regarding your Ouyniei MJXFJ-150-A1 Composite Filter, please refer to the documentation provided with your original air purification system or contact the Ouyniei customer service through the retailer where the product was purchased. Please have your purchase details ready when contacting support.