Wax Thermostatic Element LG039X

• Narrowest standard-force active window in the Legom range – Active temperature span of only 7°C (30°C to 37°C) demands the element deliver all its working stroke within a tightly defined band near body temperature, requiring highly precise wax formulation and manufacturing
• High testing load of 90N – The highest testing load among standard-force (5N/mm) Legom models, providing strong actuation force within the narrow 7°C window suited for spring-loaded valve assemblies requiring firm piston engagement
• Accelerating stroke within the narrow window – Stroke increases from 0.72mm in the first 4°C band (30°C~34°C) to 1.96mm in the final 3°C band (34°C~37°C), delivering more than 2.5× the travel in a shorter temperature span as the element approaches its upper active limit
• Stroke reference at 30°C – Referenced at the lower edge of the active window, providing a precise dimensional baseline for valve assembly design at the exact point where actuation begins
• Body-temperature activation range – The 30°C to 37°C window corresponds directly to human body temperature, making the LG039X appropriate for body-contact thermostatic safety devices and hygiene-sensitive plumbing applications
• Patented wax formula – Proprietary Legom formulation delivers superior sensitivity and temperature-response accuracy versus standard wax elements
• ACS and WRAS certified – Passed European experimental institution product certification, confirming suitability for potable water and HVAC applications in international markets
• Rated for 100,000 cycles – Exceptional service life verified through rigorous lifecycle testing, ensuring reliable long-term performance in high-use installations
• OEM and ODM customization available – Temperature range, working stroke, and maximum load can be customized to suit specific product requirements

Temperature vs. Stroke

Stroke values measured during heating-up cycle. Cooling-down cycle may exhibit slight hysteresis typical of wax thermostatic elements. Refer to the Temperature VS. Stroke curve in the Datasheet for the full graphical representation.

• Body-temperature thermostatic safety devices – The 30°C to 37°C active window corresponds to human body temperature range, making the LG039X suited for thermostatic assemblies in shower valves, washbasins, and bathing fixtures requiring precise response at body-contact water temperatures
• Thermostatic mixing valves for sensitive applications – Applied in TMV assemblies serving hospitals, care homes, and facilities for vulnerable users where the thermostatic element must respond decisively and forcefully within a narrow temperature band near body temperature
• Automotive engine cooling systems – Used in engine thermostats requiring high-force, narrow-band actuation at the lower end of the engine operating temperature range during initial warm-up phases
• Sanitary and medical equipment – Integrated into precision thermostatic valve assemblies in clinical and hygiene-sensitive environments where tight temperature control within a few degrees of body temperature is a safety requirement
• HVAC systems requiring precise low-range control – Applied in thermostatic control assemblies where actuation must occur within a tightly defined 7°C window in the comfort temperature range without response outside that band
• Shipping, military, and other industries – Suitable for demanding environments requiring high-force, self-acting thermostatic control within a precisely defined narrow temperature window

• The LG039X must be installed in direct contact with the fluid whose temperature it is intended to sense. For narrow-band elements, even small errors in sensing position can shift the effective activation temperature outside the intended 30°C to 37°C window
• Ensure the element is fully immersed in the flow path within the host valve or assembly. Partial immersion is especially problematic for narrow-band elements as it significantly reduces sensing accuracy and actuation precision
• Do not expose the element to temperatures exceeding 90°C, as sustained exposure above the maximum rated temperature may permanently degrade the wax charge and alter the calibrated narrow-band response
• Avoid applying forces exceeding the maximum load of 140N to the piston during assembly or operation
• The host valve or actuator assembly must provide adequate spring-back force to reset the piston on cooling. With a testing load of 90N, ensure the return spring is rated to provide sufficient reset force after the element reaches 37°C
• Keep the element strictly away from external heat sources not part of the intended sensing medium. Stray heat is especially impactful for narrow-band elements and can trigger actuation well outside the intended 30°C to 37°C window
• For OEM integration, confirm three key parameters in writing before finalizing the order: temperature range, working stroke, and maximum load

Legom supports full OEM and ODM services for the LG039X Wax Thermostatic Element. Our engineering team can customize the activation temperature range, working stroke, and maximum load to match your product requirements. Before any commitment, written confirmation of three key performance parameters is required: temperature range, working stroke, and maximum load. All customization projects are handled with strict confidentiality. Contact us via WhatsApp or info@legomsmart.com.