AUTOOL LM 120
Manometru digital pentru colector AUTOOL LM120+
Manual de utilizare
1. Produs terminatview
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. Informații de siguranță
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.
- Nu expuneți dispozitivul la temperaturi extreme, la lumina directă a soarelui sau la umiditate.
- Handle refrigerant hoses and connections with care to prevent leaks and refrigerant burns.
- Nu încercați să reparați sau să modificați dispozitivul. Apelați la personal calificat pentru toate lucrările de service.
- 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. Conținutul pachetului
La deschiderea coletului, vă rugăm să verificați dacă toate articolele enumerate mai jos sunt prezente și în stare bună:
- 1 x AUTOOL LM120+ Digital Manifold Gauge
- 2 x Temperature Clamp Sonde
- 3 x Refrigerant Hoses (Red, Blue, Yellow)
- 1 x Manual de utilizare (acest document)
- 1 x Storage Case (if included with specific model variant)
4. Caracteristicile produsului
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.
- Afișaj digital inteligent: Provides clear and intelligent digital display of test results for pressure and temperature, reducing diagnostic time.

Figure 7: Smart Digital Display.
5. Aspectul dispozitivului și comenzile
Familiarize yourself with the components and controls of the LM120+ Digital Manifold Gauge:

Figure 8: LM120+ Digital Manifold Gauge Components.
| Nu. | Componentă | Descriere |
|---|---|---|
| 1 | Cârlig | For hanging the unit during operation. |
| 2 | Clamp-on Temperature Probe Socket | Connection point for temperature clamp sonde. |
| 3 | Display LCD | Shows pressure, temperature, and other readings. |
| 4 | Buton de funcție | Used to cycle through different functions. |
| 5 | Butonul Run/Stop | Starts or stops measurement processes. |
| 6 | Buton zero | Resets pressure readings to zero. |
| 7 | R+/R- Refrigerant Type Selection Buttons | Used to select the type of refrigerant. |
| 8 | Buton de reglare a luminii | Reglează luminozitatea afișajului. |
| 9 | Butonul de unitate | Changes measurement units (e.g., kPa, psi, bar). |
| 10 | Butonul ° C / ° F | Comută afișarea temperaturii între grade Celsius și Fahrenheit. |
| 11 | Buton de alimentare | Pornește sau oprește dispozitivul. |
| 12 | Refrigerant Observation Window | Allows visual inspection of refrigerant flow. |
| 13 | Supapă de joasă presiune | Controls flow to the low-pressure side. |
| 14 | Supapă de înaltă presiune | Controls flow to the high-pressure side. |
| 15 | 1/4 inch Low Pressure Inlet | Connection port for low-pressure hose. |
| 16 | Supapa de suprasolicitare | Eliberează excesul de presiune. |
| 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. Configurare
- Instalare baterie: 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.
- Pornire: Apăsați tasta Buton de alimentare (11) to turn on the device. The LCD display (3) should illuminate.
- Selectarea unității: Apăsați tasta Butonul de unitate (9) to cycle through available pressure units (e.g., kPa, psi, bar) and the Butonul ° C / ° F (10) for temperature units. Select your preferred units.
- Calibrare zero: Before connecting to a system, ensure all valves (13, 14) are closed and the hoses are disconnected. Press the Buton zero (6) to calibrate the pressure sensors to zero. This ensures accurate readings.
- Conectarea sondelor de temperatură: 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.
- Conectați furtunurile:
- 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.

Figura 10: Detaliat view of hose connection points.
7. Instrucțiuni de utilizare
This section outlines common operational procedures for the LM120+.
7.1. Selecting Refrigerant Type
- With the device powered on, press the 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).
- Închideți toate supapele distribuitorului.
- Apăsați tasta Buton de funcție (4) to navigate to the leakage test mode.
- Apăsați tasta Butonul Run/Stop (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.
- Presa Butonul Run/Stop (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.
- Evacuare: 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.
- Încărcare: 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. Întreținere
- curatenie: Wipe the device and hoses with a soft, damp o lavetă. Nu utilizați substanțe de curățare abrazive sau solvenți. Asigurați-vă că nu pătrunde umezeală în componentele electrice.
- Depozitare: Store the LM120+ in its original case or a protective container in a cool, dry place, away from direct sunlight and extreme temperatures.
- Înlocuire baterie: 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. Depanare
| Problemă | Cauza posibila | Soluţie |
|---|---|---|
| Dispozitivul nu pornește. | Baterii descărcate sau descărcate; instalare incorectă a bateriilor. | Înlocuiți bateriile cu altele noi, asigurând polaritatea corectă. |
| Citiri inexacte ale presiunii. | 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. |
| Afișajul este întunecat sau pâlpâie. | 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. Specificații
| Parametru | Valoare |
|---|---|
| Marca | AUTOOL |
| Numărul de model | LM 120 |
| Dimensiuni produs (L x l x H) | Aprox. 210 mm x 120 mm x 65 mm (8.27 in x 4.72 in x 2.56 in) |
| Greutatea articolului | 950 grame |
| Dimensiunea ecranului | 12 Inches (display area, not physical device size) |
| Compatibilitate cu agentul frigorific | Multiple common refrigerants (e.g., R134a, R22, R410a, etc.) |
| Unități de presiune | kPa, psi, bar (selectable) |
| Unități de temperatură | °C, °F (selectable) |
11. Garanție și asistență
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 website pentru cele mai recente date de contact.
Please have your product model number (LM 120) and purchase information ready when contacting support.
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