Wax Thermostatic Element LGX2725
The LGX2725 Electrically-Heated Wax Thermostatic Element is a voltage-actuated thermostatic element that delivers controlled mechanical stroke on electrical command, using Legom’s proprietary patented wax formula as the actuation medium. When voltage is applied, the internal heating element warms the wax charge and drives a piston stroke of 3.8 ± 0.4mm within a start response time of less than 2 minutes and full stroke completion within 6 minutes.
Available in four voltage variants — 12V, 24V, 110V, and 220V — the LGX2725 series differs from the LGX7388 series in two important ways: a smaller stroke of 3.8mm versus 4.8mm, and a higher maximum working temperature of 90°C versus 60°C, making it the appropriate choice for electrically-commanded applications in higher-temperature environments. With a maximum force of 140N, a testing force of 85N, and a durability rating of 30,000 actuation cycles over approximately 250 days of continuous cycling, the LGX2725 is suited for HVAC, plumbing, automotive, and industrial applications requiring reliable electrically-commanded valve actuation.
Key Benefits
- Electrically-commanded actuation – Activates on applied voltage rather than responding to ambient fluid temperature, enabling integration into automated control systems, timers, thermostats, and building management platforms
- Higher maximum working temperature than LGX7388 – Rated to 90°C versus 60°C for the LGX7388 series, making the LGX2725 suited for hot water and higher-temperature HVAC applications where the LGX7388 cannot be used
- Four voltage variants in one product family – Available as LGX2728 (12V), LGX2726 (24V), LGX2727 (110V), and LGX2725 (220V), covering DC low-voltage through standard AC mains voltage in a consistent form factor
- Fast response time – Start response time under 2 minutes and full stroke completion under 6 minutes, suitable for zone control and on/off valve applications
- High force output of 140N maximum – Provides sufficient actuation force for standard manifold and zone valves in underfloor heating and hydronic HVAC systems
- Verified long-term durability – Stroke length change below 8% after 30,000 cycles (approximately 250 days of 6-minute on / 6-minute off cycling)
- Patented wax formula – Proprietary Legom formulation delivers consistent, repeatable stroke output with each electrical actuation cycle
- ACS and WRAS certified – Passed European experimental institution product certification, confirming suitability for potable water and HVAC applications in international markets
- OEM and ODM customization available – Voltage, stroke, force, and response time can be customized for specific product requirements
Technical Specifications
| Parameter | Specification |
|---|---|
| Models | LGX2725 / LGX2726 / LGX2727 / LGX2728 |
| Working Voltage | 12V / 24V / 110V / 220V |
| Material | Copper |
| Maximum Force | 140N |
| Minimum Force | 45N |
| Testing Force | 85N |
| Stroke | L = 3.8 ± 0.4mm |
| Max Working Temperature | 90°C |
| Start Response Time | < 2 minutes |
| Finish Response Time | < 6 minutes |
| Durability | 30,000 cycles (≈ 250 days); stroke change < 8% |
| Certification | ACS, WRAS |
All Models and Specifications
| Item No | Voltage | Resistance | Stroke (mm) |
|---|---|---|---|
| LGX2725 | 220V | 6.5KΩ ± 2KΩ | 3.8 ± 0.4 |
| LGX2727 | 110V | 1250Ω ± 250Ω | 3.8 ± 0.4 |
| LGX2726 | 24V | 125Ω ± 25Ω | 3.8 ± 0.4 |
| LGX2728 | 12V | 25Ω ± 5KΩ | 3.8 ± 0.4 |
Note: The 12V resistance value (25Ω ± 5KΩ) as shown in the datasheet has an unusually wide tolerance. Please confirm this specification with the Legom technical team before finalizing an OEM order for the LGX2728 variant.
Application & Use Cases
- Electrically-controlled zone valves in hot water systems – The 90°C max working temperature makes the LGX2725 suited for zone valve applications in domestic hot water, high-temperature underfloor heating, and radiator circuits where the LGX7388 series cannot be used
- Automated plumbing and HVAC control systems – Applied in motorized valve assemblies for automated zone control, remote shut-off, and time-scheduled flow management in both hot and cold water circuits
- Building automation and smart home systems – The 24V variant (LGX2726) integrates directly with standard BMS outputs and smart thermostat controllers using 24V switching signals for zone control
- Automotive and industrial flow control – Used in electrically-commanded fluid circuit valves for automotive cooling systems, industrial process lines, and thermal management applications requiring on-demand actuation
- Sanitary and medical equipment – Applied in electrically-controlled mixing and diverting valves where valve actuation must be commanded by a control system in high-temperature water environments
- Military and specialty applications – Suitable for electrically-actuated valve assemblies in demanding environments at elevated temperatures where conventional solenoid or motor-driven solutions are less appropriate
Installation Notes
- Select the correct voltage variant before ordering — LGX2728 (12V), LGX2726 (24V), LGX2727 (110V), or LGX2725 (220V). Applying incorrect voltage will prevent actuation or damage the heating element
- Ensure the power supply voltage matches the element specification. Resistance values differ significantly between variants and are not interchangeable
- The element requires up to 2 minutes to begin stroke and up to 6 minutes to reach full stroke. Design control system timing accordingly
- After power is removed, the element cools and retracts passively. Ensure the host valve assembly provides adequate spring-back force to reset the piston on cooling
- Do not expose the element to ambient temperatures exceeding 90°C, as this reduces the temperature differential available for wax expansion during electrical heating
- Avoid applying forces exceeding the maximum force of 140N to the piston during assembly or operation
- For OEM integration, confirm four key parameters in writing before finalizing the order: working voltage, stroke, response time requirement, and maximum force
Frequently Asked Questions
What is the difference between the LGX2725 and LGX7388 series?
Both series are electrically-heated wax thermostatic elements with the same force ratings, voltage options, response times, and durability specifications. The key differences are stroke output and maximum working temperature. The LGX2725 delivers a smaller stroke of 3.8mm versus 4.8mm for the LGX7388, and supports a higher maximum working temperature of 90°C versus 60°C. Choose the LGX2725 when the application involves hot water or high-temperature environments above 60°C, or when a smaller stroke is mechanically preferable. Choose the LGX7388 when a larger 4.8mm stroke is required and operating temperatures stay below 60°C.
Which voltage variant should I choose?
Select the variant matching your control system output voltage. LGX2728 (12V) suits DC low-voltage automotive and control systems. LGX2726 (24V) is compatible with standard building automation and smart thermostat outputs. LGX2727 (110V) and LGX2725 (220V) are for direct mains-voltage applications. All four variants deliver the same 3.8mm stroke and force specifications.
How long does the LGX2725 take to actuate?
The element begins responding within 2 minutes of power being applied and reaches full stroke within 6 minutes. These times assume standard ambient conditions. Higher ambient temperatures may slightly reduce response time; lower ambient temperatures may slightly increase it.
What is the durability rating?
The element is tested by cycling power on for 6 minutes then off for 6 minutes repeatedly. After 30,000 such cycles — approximately 250 days of continuous cycling — the stroke length change must remain below 8% of the original value.
What certifications does the LGX2725 hold?
The LGX2725 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.
Can the LGX2725 be customized for different voltage, stroke, or force requirements?
Yes. Legom offers full OEM and ODM customization for the electrically-heated element series including working voltage, stroke, response time, and maximum force. Written confirmation of these parameters is required before any customization project begins. Contact us via WhatsApp or email to discuss your requirements.
OEM & ODM Customization
Legom supports full OEM and ODM services for the LGX2725 Electrically-Heated Wax Thermostatic Element series. Our engineering team can customize working voltage, stroke, response time, and maximum force to match your product requirements. Before any commitment, written confirmation of key performance parameters is required: working voltage, stroke, maximum force, and response time. 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.
