huangirl AOJ-20H
Infrared Thermometer User Manual
Models: AOJ-20A, AOJ-20B, AOJ-20C, AOJ-20D, AOJ-20E, AOJ-20F, AOJ-20H, AOJ-20M, AOJ-20T, AOJ-20R, AOJ-20Y
1. Introduction
Thank you for choosing the huangirl Infrared Thermometer. This device is designed for safe, accurate, and rapid temperature measurement for individuals of all ages, including infants, children, and adults. It offers versatile measurement modes for forehead, ear, and object temperatures, ensuring comprehensive health monitoring. Please read this manual thoroughly before use to ensure proper operation and to maintain the device's longevity.
2. Safety Information
To ensure safe operation and accurate readings, please observe the following precautions:
- Do not use the thermometer for purposes other than those specified in this manual.
- Keep the device away from water and direct sunlight.
- Avoid dropping the thermometer or subjecting it to strong impacts.
- Do not attempt to disassemble or repair the device yourself. Contact qualified service personnel for assistance.
- Store the thermometer in a dry place, away from extreme temperatures and humidity.
- Keep out of reach of children. Small parts may pose a choking hazard.
- Clean the probe gently with an alcohol swab after each use to ensure hygiene and accuracy.
- Consult a medical professional if you have concerns about temperature readings or health conditions.
3. Product Overview
3.1 Key Features
The huangirl Infrared Thermometer offers several advanced features for convenient and reliable temperature measurement:
- Non-Contact & Hygienic Design: Measures temperature from 1-2 inches away, reducing cross-contamination.
- Instant, Accurate Results: Provides precise readings in approximately 1 second with clinical-grade accuracy (±0.4°F).
- Dual-Mode Functionality: Capable of measuring both body and object temperatures.
- User-Friendly Display: Features a large LCD screen with three color-coded displays for different temperature levels and clear readings day or night.
- Mute Mode: Quiet vibration alerts for results without disturbing sleep.
- Memory Function: Stores up to 40 previous readings for easy tracking.
- Unit Conversion: Easily switch between Fahrenheit (℉) and Celsius (℃).
- Auto-Shutoff: Energy-efficient design to preserve battery life.

Figure 1: The huangirl Infrared Thermometer, Model AOJ-20H, showing its digital display and measurement button.

Figure 2: The thermometer with its protective probe cover removed, ready for use.
3.2 Included Components
The product package typically includes the following items:
- Infrared Thermometer
- Pouch for storage
- AAA Batteries (2, typically included)
- User Manual (this document)
4. Setup
4.1 Battery Installation
The thermometer requires 2 AAA batteries for operation. Follow these steps to install or replace batteries:
- Locate the battery compartment cover on the back of the thermometer.
- Slide the cover downwards to open the compartment.
- Insert two AAA batteries, ensuring the correct polarity (+ and -) as indicated inside the compartment.
- Slide the battery compartment cover back into place until it clicks securely.

Figure 3: Illustration of the battery compartment and the switch for Fahrenheit/Celsius conversion.
5. Operating Instructions
5.1 Taking a Measurement (Forehead/Ear/Object)
The thermometer supports multiple measurement modes. Ensure the correct mode is selected for accurate readings.
- Power On: Press the measurement button once to turn on the thermometer. The display will show the last reading or "---".
- Select Mode: The thermometer automatically defaults to forehead mode when the probe cover is on. Remove the probe cover for ear mode. For object temperature, ensure the device is in the correct mode (refer to specific model instructions if different from body mode).
- Positioning:
- Forehead Mode: Hold the thermometer 1-2 inches (2-5 cm) from the center of the forehead.
- Ear Mode: Gently insert the probe into the ear canal.
- Object Mode: Point the thermometer at the object whose temperature you wish to measure.
- Measure: Press the measurement button again. The reading will appear on the display within approximately 1 second.
- Interpretation: The LCD screen will display the temperature and may change color (e.g., green for normal, yellow for elevated, red for fever) depending on the reading.

Figure 4: Demonstrating the proper technique for both forehead and ear temperature measurements.

Figure 5: The thermometer provides rapid temperature readings in approximately one second.
5.2 Switching Temperature Units (°F/°C)
To switch between Fahrenheit and Celsius, follow these steps:
- Open the battery compartment cover (refer to Section 4.1).
- Locate the small switch inside the battery compartment.
- Toggle the switch to select either ℉ (Fahrenheit) or ℃ (Celsius).
- Close the battery compartment cover securely. The display will now show readings in the selected unit.
5.3 Mute Mode
The mute mode allows for silent temperature measurements, ideal for not disturbing sleeping individuals. To activate or deactivate mute mode:
- With the thermometer powered on, press and hold the measurement button for approximately 5 seconds.
- The device will toggle between mute and unmute modes, indicated by a bell icon on the display.

Figure 6: The mute mode feature, allowing for silent temperature readings, useful when a baby is sleeping.
5.4 Memory Function
The thermometer can store up to 40 previous temperature readings, allowing you to track changes over time. To access stored memories:
- With the thermometer powered off, press the measurement button briefly.
- The display will show the last reading. Press the button repeatedly to cycle through previous readings.
- The memory number will be displayed alongside the temperature.

Figure 7: The thermometer's ability to store up to 40 historical temperature records, useful for tracking trends.
6. Maintenance and Care
Proper maintenance ensures the longevity and accuracy of your thermometer:
- Cleaning the Probe: After each use, especially for ear measurements, gently wipe the probe with an alcohol swab (70% isopropyl alcohol). Allow it to air dry completely before storing.
- Cleaning the Body: Use a soft, dry cloth to clean the body of the thermometer. Do not use abrasive cleaners or immerse the device in water.
- Storage: Store the thermometer in its protective pouch in a cool, dry place, away from direct sunlight, dust, and extreme temperatures.
- Battery Replacement: Replace batteries when the low battery indicator appears on the display. Remove batteries if the device will not be used for an extended period.
7. Troubleshooting
If you encounter issues with your thermometer, refer to the table below for common problems and solutions:
| Problem | Possible Cause | Solution |
|---|---|---|
| Device does not power on. | Dead or incorrectly installed batteries. | Replace batteries with new AAA batteries, ensuring correct polarity. |
| Inaccurate readings. | Dirty probe, incorrect measurement distance/position, or environmental factors. | Clean the probe. Ensure correct positioning and distance. Avoid drafts or extreme temperatures during measurement. Allow device to acclimate to room temperature for 30 minutes. |
| "LO" or "HI" displayed. | Temperature is outside the measurable range. | Ensure the measurement is within the specified operating range (e.g., 89.6°F-109.2°F for body temperature). |
| Display shows "Err". | System error or malfunction. | Remove batteries, wait 1 minute, then reinsert. If error persists, contact customer support. |
8. Technical Specifications
| Specification | Detail |
|---|---|
| Model Name | Infrared Thermometer AOJ-20H (and other AOJ-20 series models) |
| Measurement Range (Body) | Typically 89.6°F - 109.2°F (32.0°C - 42.9°C) |
| Measurement Range (Object) | Typically 32.0°F - 212.0°F (0.0°C - 100.0°C) |
| Accuracy | ±0.4°F (±0.2°C) |
| Measurement Time | Approx. 1 second |
| Memory Storage | 40 readings |
| Display Type | Digital LCD with backlight |
| Power Source | 2 x AAA batteries (included) |
| Automatic Shut-off | Yes, to conserve battery life |
| Dimensions | Approx. 6.3 inches (length) |
| Weight | Approx. 4.5 ounces (with batteries) |
9. Warranty and Customer Support
The huangirl Infrared Thermometer is manufactured under strict quality standards. While specific warranty details may vary by region or retailer, most products come with a limited warranty covering manufacturing defects from the date of purchase. Please retain your purchase receipt as proof of purchase.
For technical support, troubleshooting assistance beyond this manual, or warranty claims, please contact the retailer or the manufacturer directly. Contact information can typically be found on the product packaging or the brand's official website.
Manufacturer: Shenzhen AOJ Medical Technology Co., Ltd.
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