1. ຜະລິດຕະພັນເກີນview
The AUTOOL LM120+ Digital Manifold Gauge is a professional instrument designed for comprehensive testing and maintenance of HVAC and refrigeration systems. It provides accurate digital readings for pressure, temperature, and vacuum, facilitating efficient diagnosis and servicing of air conditioners and refrigerators. This kit includes the main gauge unit, temperature probes, and connecting hoses, offering a complete solution for refrigerant management.

Figure 1: AUTOOL LM120+ Digital Manifold Gauge and included accessories.
2. ຂໍ້ມູນຄວາມປອດໄພ
Please read and understand all safety warnings and instructions before operating the AUTOOL LM120+ Digital Manifold Gauge. Failure to follow these instructions may result in equipment damage, personal injury, or property damage.
- Always wear appropriate personal protective equipment (PPE), including safety glasses and gloves, when working with refrigerants.
- Ensure proper ventilation in the work area to prevent accumulation of refrigerant gases.
- ຢ່າໃຫ້ອຸປະກອນຖືກອຸນຫະພູມສູງ ຫຼື ແສງແດດໂດຍກົງ ຫຼື ຄວາມຊຸ່ມ.
- Handle refrigerant hoses and connections with care to prevent leaks and refrigerant burns.
- ຢ່າພະຍາຍາມສ້ອມແປງ ຫຼື ດັດແປງອຸປະກອນ. ໃຫ້ແນະນຳການບໍລິການທັງໝົດໄປຫາພະນັກງານທີ່ມີຄຸນວຸດທິ.
- Verify that the selected refrigerant type on the gauge matches the refrigerant in the system being tested.
- Keep the device away from children and unauthorized persons.
3. ເນື້ອໃນຊຸດ
ເມື່ອເປີດຊຸດ, ກະລຸນາກວດສອບວ່າທຸກລາຍການທີ່ລະບຸໄວ້ຂ້າງລຸ່ມນີ້ແມ່ນຢູ່ ແລະຢູ່ໃນສະພາບດີ:
- 1 x AUTOOL LM120+ Digital Manifold Gauge
- 2 x Temperature Clamp ຍານສຳຫຼວດ
- 3 x Refrigerant Hoses (Red, Blue, Yellow)
- 1 x ຄູ່ມືຜູ້ໃຊ້ (ເອກະສານນີ້)
- 1 x Storage Case (if included with specific model variant)
4. ຄຸນລັກສະນະຂອງຜະລິດຕະພັນ
The AUTOOL LM120+ offers a range of advanced features for precise HVAC system analysis:
- Evaporation Pressure & Temperature Test: Measures the maximum pressure when refrigerant changes from liquid to gas and the lowest temperature during this phase. This helps assess the efficiency of the cooling cycle.

Figure 2: Evaporation Pressure and Temperature Test display.
- Condensing Pressure & Temperature Test: Determines the minimum pressure when refrigerant changes from gas to liquid and the maximum temperature during this phase. Lower values indicate higher cooling cycle efficiency.

Figure 3: Condensing Pressure and Temperature Test display.
- High / Low Pressure Temperature Test: Measures the temperature of the refrigerant within the high-pressure and low-pressure pipelines of the air conditioning system.

Figure 4: High/Low Pressure Temperature Test display.
- Pressure Leakage Test: Calculates the pressure difference between an initial and a second test pressure to identify potential refrigerant leaks in the system.

Figure 5: Pressure Leakage Test display.
- Refrigerant Type Setting & Observation Window: Allows selection of the appropriate refrigerant type for accurate measurements and provides a viewable window to observe the refrigerant filling status.

Figure 6: Refrigerant Type Setting and Observation Window.
- ຈໍສະແດງຜົນດິຈິຕອນອັດສະລິຍະ: Provides clear and intelligent digital display of test results for pressure and temperature, reducing diagnostic time.

Figure 7: Smart Digital Display.
5. ການຈັດວາງອຸປະກອນ ແລະການຄວບຄຸມ
Familiarize yourself with the components and controls of the LM120+ Digital Manifold Gauge:

Figure 8: LM120+ Digital Manifold Gauge Components.
| ບໍ່. | ອົງປະກອບ | ລາຍລະອຽດ |
|---|---|---|
| 1 | ຮູ | For hanging the unit during operation. |
| 2 | Clamp-on Temperature Probe Socket | Connection point for temperature clamp ຍານ ສຳ ຫຼວດ. |
| 3 | ຈໍ LCD | Shows pressure, temperature, and other readings. |
| 4 | ປຸ່ມຟັງຊັນ | Used to cycle through different functions. |
| 5 | ປຸ່ມແລ່ນ/ຢຸດ | Starts or stops measurement processes. |
| 6 | ປຸ່ມສູນ | Resets pressure readings to zero. |
| 7 | R+/R- Refrigerant Type Selection Buttons | Used to select the type of refrigerant. |
| 8 | ປຸ່ມຫຼຸດແສງ | ປັບຄວາມສະຫວ່າງຂອງຈໍສະແດງຜົນ. |
| 9 | ປຸ່ມໜ່ວຍ | Changes measurement units (e.g., kPa, psi, bar). |
| 10 | ° C / ° F ປຸ່ມ | ສະຫຼັບການສະແດງອຸນຫະພູມລະຫວ່າງເຊວຊີ ແລະຟາເຣນຮາຍ. |
| 11 | ປຸ່ມເປີດປິດ | ເປີດ ຫຼື ປິດອຸປະກອນ. |
| 12 | Refrigerant Observation Window | Allows visual inspection of refrigerant flow. |
| 13 | ວາວຄວາມກົດດັນຕ່ໍາ | Controls flow to the low-pressure side. |
| 14 | ວາວຄວາມກົດດັນສູງ | Controls flow to the high-pressure side. |
| 15 | 1/4 inch Low Pressure Inlet | Connection port for low-pressure hose. |
| 16 | ວາວບັນເທົາ | ປ່ອຍຄວາມກົດດັນເກີນ. |
| 17 | 1/4 inch High Pressure Inlet | Connection port for high-pressure hose. |
| 18 | Refrigerant Inlet / Vacuum Pump Inlet | Central connection for refrigerant charging or vacuum pump. |
6. ຕັ້ງຄ່າ
- ການຕິດຕັ້ງຫມໍ້ໄຟ: Open the battery compartment on the back of the unit and insert the required batteries (typically AA or AAA, refer to device markings if present). Ensure correct polarity.
- ເປີດ: ກົດ ປຸ່ມເປີດປິດ (11) to turn on the device. The LCD display (3) should illuminate.
- ການຄັດເລືອກໜ່ວຍ: ກົດ ປຸ່ມໜ່ວຍ (9) to cycle through available pressure units (e.g., kPa, psi, bar) and the ° C / ° F ປຸ່ມ (10) for temperature units. Select your preferred units.
- ການປັບທຽບສູນ: Before connecting to a system, ensure all valves (13, 14) are closed and the hoses are disconnected. Press the ປຸ່ມສູນ (6) to calibrate the pressure sensors to zero. This ensures accurate readings.
- Connect Temperature Probes: Plug the temperature clamp probes into the Clamp-on Temperature Probe Sockets (2) on the top of the unit. Attach the clamps securely to the high and low-pressure lines of the HVAC system.

Figure 9: Connecting temperature probes and hoses.
- ເຊື່ອມຕໍ່ທໍ່:
- Connect the blue hose to the Low Pressure Inlet (15) on the gauge and to the low-pressure service port of the HVAC system.
- Connect the red hose to the High Pressure Inlet (17) on the gauge and to the high-pressure service port of the HVAC system.
- Connect the yellow (or central) hose to the Refrigerant Inlet / Vacuum Pump Inlet (18) on the gauge. This hose will be used for vacuuming, charging, or connecting to a recovery unit.

ຮູບທີ 10: ລາຍລະອຽດ view of hose connection points.
7. ຄໍາແນະນໍາການດໍາເນີນງານ
This section outlines common operational procedures for the LM120+.
7.1. Selecting Refrigerant Type
- ເມື່ອອຸປະກອນເປີດຢູ່, ໃຫ້ກົດປຸ່ມ R+/R- Buttons (7) to scroll through the available refrigerant types (e.g., R134a, R22, R410a).
- Select the refrigerant type that matches the system you are working on. This is crucial for accurate pressure-temperature conversions.
7.2. Performing Pressure and Temperature Tests
- Ensure hoses and temperature probes are correctly connected to the system.
- Slowly open the high-pressure (red) and low-pressure (blue) valves on the manifold to allow refrigerant to flow into the gauge.
- The LCD display will show real-time pressure readings for both high and low sides, along with corresponding saturation temperatures based on the selected refrigerant.
- The temperature probes will display the actual line temperatures (T1 and T2).
- Compare the saturation temperatures with the actual line temperatures to determine superheat and subcooling, which are critical for system diagnosis.
7.3. Performing a Pressure Leakage Test
- Connect the gauge to the system and pressurize it to the desired test pressure (ensure system can handle the pressure).
- ປິດວາວ manifold ທັງໝົດ.
- ກົດ ປຸ່ມຟັງຊັນ (4) to navigate to the leakage test mode.
- ກົດ ປຸ່ມແລ່ນ/ຢຸດ (5) to start the leakage test timer. The gauge will record the initial pressure.
- Allow the test to run for a specified period (e.g., 15-30 minutes, or as per system manufacturer's recommendations).
- The display will show the elapsed time and the pressure difference. A significant drop in pressure indicates a leak.
- ກົດ ປຸ່ມແລ່ນ/ຢຸດ (5) again to stop the test.
7.4. Refrigerant Charging/Evacuation
The LM120+ can be used in conjunction with a vacuum pump and refrigerant tank for system evacuation and charging. Always refer to the specific HVAC system's service manual for proper procedures and refrigerant amounts.
- ການຍົກຍ້າຍ: Connect the yellow hose to a vacuum pump. Open the manifold valves and the vacuum pump valve to evacuate the system to the desired vacuum level. Monitor the vacuum reading on the gauge.
- ການສາກໄຟ: After evacuation, close the manifold valves and disconnect the vacuum pump. Connect the yellow hose to a refrigerant tank. Purge the yellow hose of air. Slowly open the appropriate manifold valve (low side for vapor charge, high side for liquid charge with caution) to allow refrigerant into the system. Monitor pressure and temperature readings.
8. ບໍາລຸງຮັກສາ
- ທໍາຄວາມສະອາດ: Wipe the device and hoses with a soft, damp ຜ້າ. ຢ່າໃຊ້ນໍ້າຢາທໍາຄວາມສະອາດທີ່ມີສີຂັດ ຫຼື ຕົວລະລາຍ. ຮັບປະກັນວ່າບໍ່ມີຄວາມຊຸ່ມຊື່ນເຂົ້າໄປໃນອຸປະກອນໄຟຟ້າ.
- ການເກັບຮັກສາ: Store the LM120+ in its original case or a protective container in a cool, dry place, away from direct sunlight and extreme temperatures.
- ການປ່ຽນແບັດເຕີຣີ: If the display becomes dim or the device does not power on, replace the batteries. Ensure the device is off before replacing batteries.
- Hose and Seal Inspection: Regularly inspect hoses for cracks, wear, or damage. Check O-rings and seals on connections for integrity to prevent leaks. Replace worn components as needed.
9. ການແກ້ໄຂບັນຫາ
| ບັນຫາ | ສາເຫດທີ່ເປັນໄປໄດ້ | ການແກ້ໄຂ |
|---|---|---|
| ອຸປະກອນບໍ່ເປີດ. | ຫມໍ້ໄຟຕ່ໍາຫຼືຕາຍ; ການຕິດຕັ້ງຫມໍ້ໄຟບໍ່ຖືກຕ້ອງ. | ປ່ຽນແບັດໃໝ່, ຮັບປະກັນການຂົ້ວທີ່ຖືກຕ້ອງ. |
| ການອ່ານຄວາມດັນທີ່ບໍ່ຖືກຕ້ອງ. | Gauge not zeroed; incorrect refrigerant selected; sensor malfunction; hose leaks. | Perform zero calibration; verify refrigerant type; check hose connections for leaks; contact support if issue persists. |
| Temperature readings are incorrect or absent. | Temperature probes not connected properly; damaged probes. | Ensure probes are fully inserted into sockets; check probe cables for damage; replace probes if faulty. |
| ຈໍສະແດງຜົນແມ່ນມືດ ຫຼືກະພິບ. | Low batteries; display settings. | Replace batteries; use the Dimming Button (8) to adjust brightness. |
| Cannot select refrigerant type. | Buttons not responding; device malfunction. | Ensure buttons are pressed firmly; restart the device; contact support. |
10. ຂໍ້ມູນຈໍາເພາະ
| ພາລາມິເຕີ | ມູນຄ່າ |
|---|---|
| ຍີ່ຫໍ້ | ອັດຕະໂນມັດ |
| ໝາຍເລກຕົວແບບ | LM 120 |
| ຂະໜາດສິນຄ້າ (L x W x H) | ປະມານ. 210ມມ x 120ມ x 65ມມ (8.27ນິ້ວ x 4.72ນິ້ວ x 2.56ນິ້ວ) |
| ນ້ໍາຫນັກລາຍການ | 950 ກຣາມ |
| ຂະໜາດໜ້າຈໍ | 12 Inches (display area, not physical device size) |
| ຄວາມເຂົ້າກັນໄດ້ຂອງເຄື່ອງເຮັດຄວາມເຢັນ | Multiple common refrigerants (e.g., R134a, R22, R410a, etc.) |
| ຫນ່ວຍຄວາມດັນ | kPa, psi, bar (selectable) |
| ຫົວໜ່ວຍອຸນຫະພູມ | °C, °F (selectable) |
11. ການຮັບປະກັນແລະການສະຫນັບສະຫນູນ
For warranty information, technical support, or service inquiries regarding your AUTOOL LM120+ Digital Manifold Gauge, please contact AUTOOL customer service directly. Refer to the product packaging or the official AUTOOL webເວັບໄຊສໍາລັບລາຍລະອຽດການຕິດຕໍ່ໃນປະຈຸບັນຫຼາຍທີ່ສຸດ.
Please have your product model number (LM 120) and purchase information ready when contacting support.





