Wax Thermostatic Element LG5701
The LG5701 Wax Thermostatic Element is the most comprehensively characterized thermostatic actuator in the Legom wax element range, featuring six specified stroke segments across a 15°C to 90°C operating span. Built with Legom’s proprietary patented wax formula, it delivers consistent, repeatable stroke actuation across a rated lifespan of 100,000 cycles. It has passed European product certification by accredited institutions including ACS and WRAS.
With overlapping and sequential stroke specifications covering every critical temperature sub-band from 15°C through 90°C, the LG5701 is designed for OEM valve engineers who need precise actuation data at multiple points across the full operating range. The stroke profile includes a secondary deceleration zone at 45°C to 60°C (0.86mm), a feature shared with the LGA253 but extended here across a broader and more detailed characterization window. Constructed from copper with a maximum load of 140N and a spring rate of 5N/mm.
Key Benefits
- Most detailed stroke characterization in the Legom range – Six specified stroke segments provide OEM engineers with comprehensive actuation data across every critical temperature band from 15°C to 90°C
- Dual deceleration zones – Reduced stroke at 38°C~45°C (1.4mm) and 45°C~60°C (0.86mm) creates two distinct staged responses within the overall actuation profile, enabling complex valve behavior without multiple components
- Cumulative stroke data at key milestones – Total stroke specifications at 15°C~50°C (4 ± 0.3mm) and 15°C~90°C (5.4mm max) provide system designers with reference points for valve travel at intermediate and full-span conditions
- Wide operating span from 15°C – Activation begins at 15°C, earlier than most Legom models, covering the full range from near-ambient through high HVAC operating temperatures
- 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
- Copper construction – Corrosion-resistant material ensures long-term durability in wet and thermally cycled environments
- OEM and ODM customization available – Temperature range, working stroke, and maximum load can be customized to suit specific product requirements
Technical Specifications
| Parameter | Specification |
|---|---|
| Model | LG5701 |
| Material | Copper |
| Maximum Load | 140N |
| Minimum Load | 45N |
| Testing Load | 55N |
| Spring Rate | 5N/mm |
| Maximum Temperature | 90°C |
| Stroke | L = 20 ± 0.3mm at 38°C, 45N |
| Lifespan | 100,000 cycles |
| Certification | ACS, WRAS |
Temperature vs. Stroke
| Temperature (°C) | Stroke (mm) |
|---|---|
| 15°C ~ 38°C | 2 ± 0.2 |
| 38°C ~ 45°C | 1.4 ± 0.125 |
| 35°C ~ 45°C | 2 ± 0.2 |
| 45°C ~ 60°C | 0.86 ± 0.12 |
| 15°C ~ 50°C | 4 ± 0.3 |
| 15°C ~ 90°C | 5.4 (Max) |
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.
Application & Use Cases
- Complex thermostatic mixing valves – The six-stage stroke profile with dual deceleration zones makes the LG5701 suited for advanced TMV designs requiring precisely staged valve opening behavior across multiple temperature thresholds
- Automotive engine cooling systems – Applied in engine thermostats and cooling circuit controls where the element must deliver a detailed, graduated response from cold-start at 15°C through full engine operating temperature
- HVAC multi-zone control assemblies – Used in thermostatic control valves where a complex, multi-stage actuation profile is required to match the thermal behavior of the heating or cooling circuit
- Anti-scald and hot water safety devices – The deceleration zone at 45°C~60°C provides a natural slowdown in valve travel at temperatures associated with scalding risk, enabling safer blended water delivery
- Sanitary and medical equipment – Integrated into precision thermostatic assemblies in hospital and clinical settings requiring detailed, staged water temperature control across multiple thresholds
- Shipping, military, and other industries – Suitable for demanding environments requiring self-acting, multi-stage thermostatic control without electrical dependency
Installation Notes
- The LG5701 must be installed in direct contact with the fluid whose temperature it is intended to sense, ensuring accurate thermostatic response across all six stages of the stroke profile
- Ensure the element is fully immersed in the flow path within the host valve or assembly. Partial immersion is particularly problematic for multi-stage elements as it can distort the staged response at closely spaced temperature boundaries
- 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 reduce stroke accuracy
- 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, as the wax element generates push force only during heating
- Keep the element away from external heat sources not part of the intended sensing medium to avoid premature or incorrect actuation across any of the six stroke stages
- For OEM integration, confirm three key parameters in writing before finalizing the order: temperature range, working stroke, and maximum load
Frequently Asked Questions
What makes the LG5701 different from other Legom wax thermostatic elements?
The LG5701 has the most detailed stroke characterization in the entire Legom wax element range, with six specified stroke segments compared to two to four rows in other models. It also features two deceleration zones within its profile, at 38°C~45°C and 45°C~60°C, where stroke rate reduces before resuming. This level of characterization makes it the appropriate choice for OEM engineers designing complex thermostatic valve mechanisms that require precise actuation data at multiple points across a broad temperature range.
How should I read the six-row stroke table?
The table contains a mix of sequential and overlapping ranges that serve different purposes. The first two rows (15°C~38°C and 38°C~45°C) describe incremental stroke in consecutive bands. The third row (35°C~45°C) is an overlapping window that gives a combined stroke view of the 35°C to 45°C zone. The fourth row (45°C~60°C) continues with the second deceleration band. The fifth row (15°C~50°C) provides a cumulative stroke reference to the 50°C milestone. The sixth row (15°C~90°C) gives the total stroke ceiling across the full operating span. Refer to the Temperature VS. Stroke curve in the Datasheet for the complete graphical representation.
What certifications does the LG5701 hold?
The LG5701 has passed European experimental institution product certification under ACS and WRAS standards, confirming its suitability for use in drinking water systems and broader HVAC and plumbing applications in certified markets.
What is the expected service life of the LG5701?
The LG5701 is rated for 100,000 actuation cycles, supporting long-term deployment in high-use installations across its full 15°C to 90°C operating range.
Can the LG5701 be customized for different temperature or stroke requirements?
Yes. Legom offers full OEM and ODM customization. If your application requires a different activation temperature, working stroke, or load specification, the engineering team can develop a customized solution. Written confirmation of three key parameters is required before any customization project begins: temperature range, working stroke, and maximum load.
How do I select the right wax thermostatic element for my product?
The key selection criteria are the required activation temperature range, the working stroke needed to actuate your valve mechanism, and the maximum load the element must deliver. If you are unsure about any of these parameters, the Legom team can assist with selection or develop a custom element. Contact us via WhatsApp or email to begin the process.
OEM & ODM Customization
Legom supports full OEM and ODM services for the LG5701 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.
Datasheet
Product information last reviewed by the Legom Technical Team. For the most current specifications, refer to the official datasheet or contact our sales team.
Custom OEM & ODM Solutions
Legom is a direct manufacturer offering end-to-end OEM and ODM services. With our in-house engineering and production capabilities, we work closely with distributors and system integrators to deliver fully customized solutions under strict NDA.
