Description
The Belimo LF24-S US is a spring return damper actuator designed for dependable on/off control in HVAC air distribution systems. Operating on 24 VAC/DC power, it provides 35 in-lb torque and consistent fail-safe performance for controlled damper positioning.
Technical Specifications
| Condition |
New/Never Used Surplus |
| Brand |
Belimo |
| Category |
Damper Actuators |
| Part Number |
LF24-S US |
| Subcategory |
Spring Return Damper Actuators |
| Actuator Type |
Damper Actuator |
| Control Type |
On/Off |
| Nominal Voltage |
AC/DC 24 V |
| Nominal Frequency |
50/60 Hz |
| Voltage Range |
AC 19.2…28.8 V / DC 21.6…28.8 V |
| Torque Output |
35 in-lb (4 Nm) |
| Spring Return |
Yes |
| Power Consumption (Operation) |
5 W |
| Power Consumption (Rest) |
2.5 W |
| Transformer Sizing |
7 VA |
| Auxiliary Switch |
1 × SPDT, adjustable 0…95° |
| Angle of Rotation |
Max. 95° |
| Running Time |
75 s / 90° |
| Protection Rating |
IP54, NEMA 2 |
| Ambient Temperature |
-22…122°F (-30…50°C) |
| Weight |
3.7 lb (1.7 kg) |
Information About LF24-S US
The LF24-S US is part of Belimo’s compact spring return damper actuator series developed for reliable airflow control and safety positioning. It incorporates an internal spring mechanism that automatically drives the damper to a defined position during power loss, supporting system protection requirements. The actuator includes an adjustable SPDT auxiliary switch and electronic overload protection to ensure accurate signaling and long-term operational stability. Designed for commercial HVAC installations, it complies with UL and CSA standards and is suitable for plenum-rated applications.
Key Features
- 35 in-lb Torque Output: Provides sufficient force for consistent operation of small to medium-sized air dampers.
- Spring Return Safety Function: Automatically moves the damper to a fail-safe position upon power interruption.
- 24 VAC/DC Power Supply: Compatible with standard low-voltage HVAC control systems.
- On/Off Control Operation: Supports simple binary damper control for ventilation and zoning functions.
- Integrated Auxiliary Switch: One adjustable SPDT switch enables position feedback or interlock signaling.
- Electronic Overload Protection: Protects the actuator across the full rotation range to extend service life.
- Selectable Rotation Direction: Allows flexible clockwise or counterclockwise mounting configurations.
The LF24-S US delivers the reliability and precision required for safe and consistent spring return damper control in commercial HVAC airflow management systems.
