AUTOOL LM55 · Pipe-Clamp Thermometer with Trend Recording
See Pipe Temperature Change as It Happens
Clamp onto pipes under 40 mm in diameter to follow live temperature readings and heating or cooling curves during HVAC, refrigeration and automotive A/C work. Save up to eight waveform sets of up to 150 seconds each and pause recording for review. The compact color display offers adjustable brightness, °C/°F units and Chinese/English operation, powered by three AAA batteries.
- Pipes Under 40 mm
- Live Temperature Curves
- 8 × 150-Second Waveform Sets
- Pause for Reading Review
- Adjustable Color Display
Key Features
Live Temperature Waveform with Eight Saved Readings
Live Numerical Reading
Read current pipe temperature directly after the clamp has stable contact.
Real-Time Waveform
Follow heating or cooling direction on a real-time temperature/time curve.
Eight Saved Records
LM55 stores and browses eight waveform sets of up to 150 seconds each; recording stops with an alert when storage is full.
Pause And Resume
Use Enter to pause and resume a live waveform recording.
Under-40 mm Clamp
The clamp is designed for pipe temperature measurement and supports applicable pipe diameters under 40mm. Measure suitable pipes smaller than 40 mm without forcing the jaws onto an oversized or irregular surface.
Color TFT Display
The 0.96-inch, 80 RGB × 160-dot TFT-LCD shows live temperature, waveforms, saved records, and settings.
Adjustable Brightness
Adjust backlight brightness from 0 to 100 to keep the screen readable in different service environments.
Selectable Units And Language
The system supports Chinese and English language options for different users and service environments. Switch between °C/°F and Chinese/English menus.
Portable Battery Power
Runs on three AAA batteries in a PA6-GF45 housing.
Product Dimensions
The LM55 measures 178 × 100 mm.
3 Years Warranty Support
Main unit: 3-year warranty. Standard accessories: 1-year warranty. Warranty Policy.
Safety & Compatibility
Keep Sensors on Suitable Clean Pipe Surfaces
Use The Conservative Temperature Boundary
The body contains a -50°C to 260°C instrument range but also warns against high-temperature points and says routine use should remain below 150°C; do not market 260°C as a safe application limit.
Do Not Force The Clamp
Use only on suitable pipes under 40 mm.
Keep Contact Stable
A dirty, loose or irregular surface can reduce reading consistency.
Store Dry
Avoid hot, humid, corrosive and poorly ventilated storage; protect the housing from rough surfaces.
Track Pipe-Temperature Trends
Use pipe-temperature trends to compare A/C system behavior under consistent operating conditions, together with the specified pressure and service checks.
Test Results
Use Pipe Temperature Trends and Stability to Support A/C Diagnosis
Stable Value
Supports a repeatable pipe-temperature observation for the same contact point and condition.
Rising Or Falling Curve
Shows direction and rate of local temperature change, which can be compared with a controlled system event.
Sudden Jump
First check clamp contact, pipe surface and movement before attributing the change to the system.
Before/After Comparison
Use the same pipe location, contact and operating condition; combine with pressure, airflow and equipment data for diagnosis.
Specifications
LM55 Specifications
| Selection Criteria | |
|---|---|
| Primary task | Single-pipe temperature trend |
| Pressure measurement | No |
Manual & Downloads
Use the Manual for Setup and Service
AUTOOL LM55 User Manual
Open the PDF manual for LM55 pipe-temperature measurement, waveform recording, saved records, clamp placement, safe battery use, maintenance, and troubleshooting.
Package
What’s Included
- LM55 Main UnitDigital pipe-clamp temperature meter.
- Included Documentation And PackagingConfirm the exact supplied documentation, packaging and any accessories for the selected order.
FAQs
Clamp Placement and Trend Questions
What Is AUTOOL LM55 Used For?
AUTOOL LM55 is a digital pipe-clamp thermometer for HVAC, refrigeration, and automotive A/C work that shows local pipe temperature as a live number and real-time curve and stores waveform records for later review.
What pipe size fits?
Suitable pipes under 40 mm diameter.
How many records can it store?
Eight waveform records of up to 150 seconds each.
Can it diagnose an A/C fault by itself?
No. Combine its pipe trend with pressure, airflow and equipment-specific information.
Can it be used to 260°C?
The instrument span extends to 260°C, but routine use is recommended below 150°C and high-temperature points should be avoided. Follow the manual’s conservative limit.
Can I Switch Between Celsius And Fahrenheit?
Yes. LM55 supports ℃ and ℉ unit switching. Enter the setup interface, select the unit option, choose the desired unit, and save the setting.
- Yes, between Celsius and Fahrenheit.
What powers it?
Three AAA batteries.
What should I check if a curve jumps?
Check contact, pipe surface and movement before interpreting it as a system change.
How Do I Maintain Reliable Clamp Contact?
Use the clamp only on suitable pipes under 40 mm. Do not force it onto oversized or irregular surfaces; stable contact is required for reliable readings.
Can LM55 Be Used On High-Temperature Points?
No. Avoid unsafe high-temperature points. Keep routine pipe measurements below 150°C unless the manual or AUTOOL support confirms the application.
Why Does The Specs Table Mention A Manual Measurement Range?
The user manual lists an instrument measurement range of -50°C to 260°C. The operating guidance also says not to clamp unsafe high-temperature points and to keep routine pipe testing below 150°C. Treat the wider instrument range as a specification, not permission for every hot-surface application.
Does LM55 Support Waveform And History Data?
Yes. LM55 can display a real-time temperature/time waveform and store 8 sets of waveform data. Each set records up to 150 seconds, and historical waveform records can be browsed later.
What Batteries Does LM55 Use?
LM55 uses a 4.5V power supply from 3 × AAA batteries. Install the batteries correctly before powering on the device.
Can The Screen Brightness Be Adjusted?
Yes. The LM55 screen brightness can be adjusted from 0 to 100 in the setup interface. This helps improve readability in different workshop environments.
Is There An LM55 Manual?
Yes. The AUTOOL LM55 user manual is available as a PDF in the Manual section above. It covers specifications, functions, operation, buttons, display, maintenance, warranty, and return service information.
What Is The Warranty For LM55?
Main unit: 3-year warranty. Standard accessories: 1-year warranty. Warranty Policy.
How Should LM55 Be Stored And Maintained?
Keep the product away from rough surfaces, regularly check tightened and connected parts, avoid corrosive liquids, and store it in a dry place. Do not store it in hot, humid, or non-ventilated environments.
Which Related AUTOOL Tools Are Listed In Quick Search?
The Quick Search section lists LM55 and related AUTOOL HVAC or A/C service tools, including LM120, LM120+, LM150, and LM160. These products are related service tools, not direct LM55 function variants.
