1. Introduction
The AUTOOL LM160 Digital Refrigeration Manifold Gauge is an auxiliary instrument designed for the installation, testing, and maintenance of refrigeration equipment such as air conditioners, refrigerators, and cold storage units. This versatile tool supports pressure tests, temperature tests, refrigerant charging, vacuum tests, and pressure leak tests. It features a built-in database of 95 types of NIST refrigerant data, making it a powerful and convenient solution for professionals in the HVAC and refrigeration industry.
Figure 1: AUTOOL LM160 Smart Digital Manifold Kit
2. Safety Information
Please read and understand all safety warnings and instructions before operating the AUTOOL LM160. Failure to do so may result in injury or damage to the equipment.
- Always wear appropriate personal protective equipment (PPE), including safety glasses and gloves, when working with refrigeration systems.
- Ensure the work area is well-ventilated.
- Do not expose the device to extreme temperatures, moisture, or corrosive environments.
- Handle refrigerant cylinders with care and follow all manufacturer guidelines.
- Only qualified personnel should perform refrigeration system maintenance.
- Disconnect power to the refrigeration system before connecting or disconnecting hoses.
3. Package Contents
The AUTOOL LM160 Digital Refrigeration Manifold Gauge kit typically includes the following items:
- 1 x AUTOOL LM160 Digital Manifold Gauge
- 2 x Clamp Temperature Probes
- 3 x Refrigerant Hoses (Red, Yellow, Blue)
- 1 x User Manual
- 1 x Carrying Case
- Hose sealing accessories
Figure 2: AUTOOL LM160 Package Contents
4. Product Overview
The AUTOOL LM160 features a robust design with engineering plastics and an anti-slip grip for durability and comfort. Its large LCD screen with backlight ensures clear readability even in low-light conditions. The device incorporates a ball valve type switch for precise control.
Figure 3: AUTOOL LM160 Product Diagram and Dimensions
Key Components:
- Temperature probe T1: Connects to the first temperature sensor.
- Temperature probe T2: Connects to the second temperature sensor.
- Display: 2.8-inch backlit LCD screen.
- Control button sound / Enter the setting interface: Button for sound control and accessing settings.
- Upward button / Turn to the next page of refrigerant selection: Navigates up or to the next page in refrigerant selection.
- Return or exit: Button to go back or exit a menu.
- UNIT: Switches pressure and temperature units.
- Downward button / Turn to the next page of refrigerant selection: Navigates down or to the next page in refrigerant selection.
- OK: Confirms selection.
- P=0 Pressure zeroing: Resets pressure readings to zero.
- Control backlight / Start up and shut down: Controls screen backlight and powers the device on/off.
- Low-pressure control knob: Controls the low-pressure valve.
- Sight glass for refrigerant flow: Allows visual inspection of refrigerant flow.
- High-pressure control knob: Controls the high-pressure valve.
- Filling hose joint / air exhaust joint: Connection point for filling hose or air exhaust.
- Low-pressure pipe connection: Connects to the low-pressure side of the system.
- Filling hose connection: Connects to the refrigerant filling hose.
- High-pressure pipe connection: Connects to the high-pressure side of the system.
- Foldable hook: For hanging the device during use.
- Handle tape: Ergonomic handle for carrying.
5. Setup
Before using the LM160, ensure all components are present and in good condition.
- Charge the Device: Ensure the LM160 has sufficient battery charge.
- Connect Temperature Probes: Connect the clamp temperature probes (T1 and T2) to their respective ports on the top of the manifold gauge.
- Connect Refrigerant Hoses: Attach the refrigerant hoses to the appropriate ports on the manifold gauge. The blue hose is typically for low pressure (LP), the red for high pressure (HP), and the yellow for service/vacuum.
- Zero Pressure: When the meter is turned on, if there are digits in the high and low-pressure display area, long-press the 'P=0' button until the readings return to zero.
- Language Setting: Navigate to the settings menu using the control buttons to select your preferred language (English, French, German, Italian, Spanish, Portuguese, Chinese, Japanese are supported).
Video 1: Demonstration of AC refrigerant recharge using the LM160.
6. Operating Instructions
6.1. Vacuum Measurement (Evacuation Mode)
This mode is used to evacuate air and moisture from the refrigeration system.
- Connect Vacuum Pump: Connect the yellow service hose from the LM160 to a vacuum pump.
- Access Evacuation Mode: On the LM160, navigate to and select the 'Evacuation' mode.
- Open Low-Pressure Valve: Open the low-pressure valve on the manifold gauge (blue knob).
- Start Vacuum Pump: Turn on the vacuum pump.
- Monitor Vacuum: The LM160 will display the current vacuum pressure, hold time, evaporation temperature of water (TH2O), ambient temperature (Tamb), and temperature difference (Delta T).
- Stop Evacuation: Once the desired vacuum level is reached and held, stop the vacuum pump and close the low-pressure valve.
Figure 4: Pressure Leak Test Screen
6.2. Refrigeration Mode
This mode provides real-time measurement of pressure and temperature data for the refrigeration system, including automatic superheat and subcooling calculations.
- Connect to System: Connect the low-pressure (blue) and high-pressure (red) hoses to the respective ports on the refrigeration system.
- Access Refrigeration Mode: On the LM160, navigate to and select the 'Refrigeration' mode.
- Select Refrigerant Type: Choose the correct refrigerant type from the built-in database (e.g., R134a, R410A) using the navigation buttons.
- Open Valves: Open the LP and HP valves on the manifold gauge.
- Monitor Data: The screen will display real-time data including:
- LP: Pressure at Low-Pressure pipe
- HP: Pressure at High-Pressure pipe
- Ev: Evaporation temperature
- Co: Condensation temperature
- T1: Evaporation temperature of measured pipe
- T2: Condensation temperature of measured pipe
- SH: Superheating evaporation temperature
- SC: Subcooling condensation temperature
- Refrigerant Charging (if needed): If charging is required, connect the yellow service hose to the refrigerant cylinder and follow standard charging procedures, monitoring the LM160 display. The visible window allows direct observation of refrigerant flow.
Figure 5: Refrigeration Mode Screen
6.3. Pressure Leak Test
This function checks the tightness of the refrigeration system.
- Isolate System: Ensure the refrigeration system is isolated and pressurized to the test pressure.
- Access Leak Test Mode: On the LM160, navigate to and select the 'Pressure Leak Test' mode.
- Start Test: The device will record the 'Start P' (initial pressure).
- Monitor Leakage: After a set period, the device will display 'Current P' (current pressure) and 'Delta P' (the difference between start and current pressure). A significant 'Delta P' indicates a leak.
6.4. Unit Conversion
Press the 'UNIT' button to cycle through available pressure units (psi, kPa, MPa, bar, inHg, kg/cm²) and temperature units (°C, °F).
6.5. Language Settings
The LM160 supports multiple languages. Access the settings menu (usually by pressing the button with a gear icon) and navigate to the language option to select your preferred language.
Figure 6: Multilingual Support
7. Specifications
Figure 7: Product Specifications
| Feature | Specification |
|---|---|
| Pressure measurement unit | psi, kPa, MPa, bar, kg/cm² |
| Temperature measurement unit | °F, °C |
| Vacuum measurement unit | Micron, hPa, mbar, mTorr, Torr |
| Pressure range | 0-870psi, 0-60kg/cm², 0-60bar (rel) |
| Temperature range | -67-257°F, -55-125°C |
| Vacuum range | (rel):-14.7-0psi, -1-0Bar |
| Overload | 942.5psi, 65bar, 65kg/cm² |
| Pressure resolution | 0.1psi, 0.01bar, 1kPa, 0.005MPa, 0.01kg/cm² |
| Temperature resolution | 0.1°F, 0.1°C |
| Vacuum resolution | 1 Micron, 1hPa, 1mbar, 1Torr, 1mToor |
| Temperature accuracy | ±0.9°F (±1), ±0.5K (±1), ±0.5°C (±1) |
| Pressure accuracy | ±0.5% of full range |
| Vacuum accuracy | ±0.5% of full range |
| Number of refrigerant species | 95 |
| Display | Backlit display, Response time: 0.5s |
8. Maintenance
- Cleaning: Wipe the device with a soft, damp cloth. Do not use abrasive cleaners or solvents.
- Storage: Store the LM160 in its carrying case in a dry, cool place when not in use.
- Battery: Keep the device charged. If storing for extended periods, charge it periodically to maintain battery health.
- Hoses and Probes: Inspect hoses and probes regularly for wear, cracks, or damage. Replace as necessary to ensure accurate readings and prevent leaks.
- Calibration: While the device is factory calibrated, periodic professional calibration may be required for critical applications.
9. Troubleshooting
- Device not turning on: Check battery charge. Ensure the power button is pressed correctly.
- Inaccurate readings: Ensure hoses are properly connected and not leaking. Verify the correct refrigerant type is selected. Perform pressure zeroing if necessary. Check temperature probe connections.
- Display issues: If the display is dim, adjust the backlight setting. If the screen is unresponsive, try restarting the device.
- Pressure not zeroing: Long-press the 'P=0' button. If the issue persists, consult support.
10. User Tips
No specific user tips were available from provided reviews or Q&A. However, general tips for digital manifold gauges include:
- Always double-check refrigerant type selection to avoid incorrect readings and potential system damage.
- Ensure all connections are tight to prevent refrigerant leaks and ensure accurate vacuum readings.
- Keep the display clean for optimal visibility, especially in varying light conditions.
11. Warranty and Support
The AUTOOL LM160 Digital Refrigeration Manifold Gauge comes with a 48-month free warranty. For technical support, troubleshooting assistance, or warranty claims, please contact AUTOOL customer service. Keep your purchase receipt as proof of purchase for warranty purposes.
Figure 8: AUTOOL 3-Year Warranty
