KOABBIT KH158
KOABBIT KH158 4-in-1 Combination Gas & Carbon Monoxide Detector User Manual
Model: KH158
Introduction
This manual provides essential information for the proper installation, operation, and maintenance of your KOABBIT KH158 4-in-1 Combination Gas & Carbon Monoxide Detector. Please read this manual thoroughly before use and retain it for future reference. This device is designed to detect natural gas, propane, methane, butane, LNG, LPG, and carbon monoxide, while also displaying temperature and humidity.
Product Features
- 4-in-1 Detection: Detects natural gas, propane, methane, butane, LNG, LPG, and carbon monoxide.
- Real-time Display: Large digital display shows carbon monoxide level (PPM), combustible gas level (%LEL), temperature (°F), and humidity (RH%).
- Audible Alarm: Emits an 85dB alarm when dangerous gas levels are detected.
- Visual Indicators: Power, Fault, and Alarm lights for quick status checks.
- Self-Test Button: Allows for manual testing of the device's functionality.
- Plug-in Design: Easy installation by plugging directly into a standard power outlet.

Image: Two KOABBIT KH158 4-in-1 Combination Gas & Carbon Monoxide Detectors, showing their digital displays with temperature, CO, gas, and humidity readings, along with power, fault, and alarm indicator lights and a self-test button.
Safety Information
Please observe the following safety precautions:
- This device is intended for indoor use only.
- Do not paint the detector. Paint can clog the sensor openings and prevent the unit from functioning properly.
- Do not block the ventilation openings on the device.
- Regularly test the detector using the self-test button.
- Do not use cleaning agents or solvents on the detector. Wipe with a slightly damp cloth.
- This detector is not a substitute for proper installation and maintenance of fuel-burning appliances, including appropriate ventilation systems.
Setup and Installation
- Unpacking: Carefully remove the detector from its packaging. Inspect for any damage.
- Power Connection: Plug the detector directly into a standard 120V AC wall outlet. Ensure the outlet is not controlled by a switch that could accidentally turn off power to the detector. The plug can rotate for flexible installation.
- Initial Warm-up: After plugging in, the device will initiate a 60-second countdown. During this period, the display may show various readings. Once the countdown is complete, a green light will illuminate, indicating normal operation.
- Optimal Placement:
- For natural gas (which rises), install the detector 12-24 inches (30-60 cm) below the ceiling and at least 6 feet (1.8 meters) away from gas appliances.
- For propane/LPG (which sinks), install the detector 6-12 inches (15-30 cm) above the floor and at least 6 feet (1.8 meters) away from gas appliances.
- For carbon monoxide, place the detector at a height where it can be heard, typically at eye level or higher, but not directly above fuel-burning appliances.
- Avoid placing near windows, doors, exhaust fans, or in direct sunlight, as these can affect sensor accuracy.

Image: A diagram illustrating the physical dimensions of the detector (4.72 inches long, 2 inches wide) and highlighting its rotatable plug for easy installation or removal from an electrical outlet.

Image: The KOABBIT KH158 detector plugged into a wall outlet in a kitchen setting, demonstrating its compact, plug-and-play installation.
Operating Instructions
Display Information:
The digital display provides real-time readings:
- Temperature: Displays in degrees Fahrenheit (°F).
- CO Level: Displays carbon monoxide concentration in Parts Per Million (PPM).
- Gas Level: Displays combustible gas concentration in %LEL (Lower Explosive Limit).
- Humidity: Displays relative humidity in RH%.

Image: The KOABBIT KH158 detector plugged into a wall, showing its digital display with readings for temperature (87°F), CO (various PPM levels in bubbles), gas (167%LEL), and humidity (45%RH) in a living room environment.
Indicator Lights:
- Green (POWER): Indicates the device is powered on and operating normally.
- Yellow (FAULT): Indicates a malfunction or sensor error. Refer to the Troubleshooting section.
- Red (ALARM): Indicates dangerous levels of gas or carbon monoxide have been detected.
Self-Test Function:
Press the SELF-TEST button to verify the alarm and display functionality. The device will briefly activate the alarm and illuminate all indicators. This test should be performed weekly.
Alarm Conditions and Actions
When the detector senses dangerous levels of combustible gas or carbon monoxide, it will:
- Emit a loud 85dB audible alarm.
- Flash the red ALARM indicator light.
- Display the detected gas concentration on the screen.
If the Alarm Sounds:
- Do not panic. Remain calm.
- Evacuate Immediately: Move everyone, including pets, to fresh air outdoors.
- Do not re-enter the premises until emergency responders have declared it safe.
- Call Emergency Services: For gas leaks, contact your gas supplier or fire department. For carbon monoxide, call the fire department.
- Identify and Address the Source: Once safe to do so, investigate the cause of the alarm. This may involve checking gas appliances, furnaces, water heaters, or other combustion sources.

Image: The KOABBIT KH158 detector positioned in a home, alongside illustrations of common sources of gas and carbon monoxide, such as a coal stove, gas water heater, and gas stove, emphasizing its role in protecting occupants.
Maintenance
- Regular Cleaning: Dust can accumulate on the detector and interfere with its operation. Gently vacuum the detector cover once a month using a soft brush attachment. Do not use water, cleaners, or solvents.
- Weekly Test: Press the SELF-TEST button weekly to ensure the alarm and display are functioning correctly.
- Avoid Obstructions: Ensure nothing is blocking the ventilation openings of the detector.
- Sensor Lifespan: Gas and CO sensors have a limited lifespan. While this device is designed for long-term use, it is recommended to replace detectors every 5-7 years for optimal performance.
Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Detector not powering on | No power to the outlet; faulty outlet; device malfunction. | Check power to the outlet. Try a different outlet. If still no power, contact support. |
| Yellow FAULT light is on/flashing | Sensor error or internal malfunction. | Unplug the device for 30 seconds and plug it back in. If the fault persists, contact support. |
| False alarm (no apparent gas/CO) | Interference from strong odors (e.g., cleaning products, paint fumes), high humidity, or sensor sensitivity. | Ventilate the area. Unplug and replug the device to reset. Ensure proper placement away from sources of interference. If false alarms continue, contact support. |
| Alarm sounds, but display shows low levels | Initial detection of rising gas/CO levels before reaching peak display. | Treat all alarms as real. Follow the "If the Alarm Sounds" protocol. |
Specifications
- Model: KH158
- Brand: KOABBIT
- Power Source: Plug-in (120V AC)
- Alarm Volume: 85dB at 1 meter
- Detected Gases: Natural Gas (Methane), Propane, Butane, LNG, LPG, Carbon Monoxide
- Detection Range (CO): 0-1000 PPM
- Detection Range (Combustible Gas): 0-10% LEL
- Temperature Display Range: 1-176 °F
- Humidity Display Range: 0-99% RH
- Material: ABS
- Dimensions: Approximately 4.72 inches (Length) x 2 inches (Width)
- Weight: Approximately 1.6 ounces
Warranty and Support
For warranty information or technical support, please refer to the contact information provided with your purchase or visit the official KOABBIT website. Please have your model number (KH158) and purchase date available when contacting support.
For further assistance, you may also refer to the KOABBIT Store on Amazon.
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