If you are installing a Belimo LF24-SR Damper Actuator on a pipe with heavy insulation, a standard mount won’t cut it. You need a valve neck extension kit to ensure your actuator doesn’t end up buried in fiberglass. Below is a technical breakdown, and hands-on video, on how to add a valve neck extension kit to a Belimo LF24-SR Damper Actuator and get it done right the first time.
When is a Valve Neck Extension Mandatory?
You should utilize an extension kit in the following circumstances:
- High-Performance Insulation: Your chilled water or steam pipes have insulation thicker than 2 inches.
- Actuator Longevity: You need to put distance between the actuator and extreme pipe temperatures to prevent electronic component degradation.
- Manual Accessibility: The manual override and position indicator must remain visible and accessible for seasonal maintenance.
Technical Specifications of the Belimo LF24-SR Damper Actuator
Before you extend, you need to know what you’re working with. The LF24-SR is a staple in building automation systems because of its reliability in safety-critical applications.
- Torque: 35 in-lb [4 Nm] – perfect for smaller dampers or valves requiring precise control.
- Control Signal: 2 to 10 VDC proportional signal, offering a high degree of modulation accuracy.
- Fail-Safe: Built-in spring return ensures the damper or valve returns to a safe position during a power loss.
Watch the Step-by-Step Video
How to Add a Valve Neck Extension Kit to a Belimo LF24-SR Damper Actuator
Before you start, ensure you have your Belimo LF24-SR Damper Actuator and the corresponding extension kit ready.
1. Zero Out the System
Ensure your valve is in the “Closed” or “Fail-Safe” position. Match the actuator’s rotation to the valve’s starting point before mounting.
BAC Pro-Tip: Misaligning these now means your controller will report “Open” when the valve is physically closed.
2. Install the Extension Housing
Slide the extension housing over the valve neck. These kits are designed specifically for Belimo’s standard mounting footprint. Ensure the housing is seated flush against the valve body before tightening the locking nuts.
3. Connect the Internal Stem & Coupler
Insert the internal stem extension through the housing. Slide the actuator down until you hear the valve stem and coupler click together. Once seated, slide the coupler lock into the downward position to prevent mechanical drift.
4. Mount the LF24-SR Actuator
Place the Belimo LF24-SR Damper Actuator onto the bracket at the top of the extension. Secure it using the standard mounting bolts provided with the actuator. If your kit includes a red centering device, use it now to align the linkage riser. This ensures the stem is perfectly vertical, preventing the “binding” that leads to premature motor failure. Tighten the four mounting screws once centered, then discard the tool.
5. Final Calibration & Adaptation
Apply power and press the Adaptation button on the LF24-SR. The actuator will run a full cycle to map its new travel limits, ensuring your 2-10VDC signal is perfectly calibrated to the extended hardware.
Why Buy Belimo from Boston Aircontrols?
When a project is on the line, you don’t have time for out-of-stock notifications from national box stores. We maintain a massive inventory of Belimo LF24-SR Damper Actuators and valve neck extension kits in our local warehouse. Order today, and we can often ship your parts the same day via UPS Ground, ensuring they reach your job site right on schedule.
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