Optimizing HVAC Efficiency with the AFS Series Differential Pressure Switches

The AFS Series of Duct Differential Pressure Switches, including the EXT-AFS-460, EXT-AFS-460-136, and EXT-AFS-460-137, represent Belimo’s latest innovation in HVAC system management. These switches are specifically designed to monitor and control air pressure within duct systems, ensuring optimal performance and energy efficiency.

Applications and Use Cases

The AFS Series switches are ideal for various HVAC applications, such as air filter monitoring, where they are perfect for detecting when an air filter becomes clogged, allowing for timely maintenance and replacement. They also provide fan overload protection by monitoring differential pressure, helping to prevent fans from operating outside their safe parameters and protecting against damage while extending their operational life. Additionally, in systems where maintaining specific air pressure levels is crucial, the AFS Series can be used for duct pressure monitoring, ensuring consistent pressure and helping to maintain overall system balance and efficiency.

Product Features

Each model in the AFS Series comes with a manual reset feature, requiring operator intervention to reset the switch after it has been triggered. This ensures that any issues are addressed before the system can resume operation, adding a layer of safety and control.

The series offers a versatile array of configurations to suit a variety of needs. For instance, the EXT-AFS-460 features a single-pole, single-throw (SPST) dry contact switch, which is ideal for basic on/off control. In contrast, the EXT-AFS-460-136 and EXT-AFS-460-137 models feature double-pole, double-throw (DPDT) switches that allow for more complex control schemes. The 136 model is designed for 120 V AC applications, while the 137 model is suited for 24 V AC applications.

All models in the series can measure differential pressures ranging from 0.4 to 12 inches WC (100 to 3000 Pa), making them versatile enough for a wide range of HVAC applications. Built with durable, high-quality materials, the AFS Series is designed to withstand the rigors of demanding HVAC environments, ensuring long-lasting reliability.

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Figure 1: EXT-AFS-460-136 double-pole, double-throw (DPDT) switch

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Figure 2: EXT-AFS-460 single-pole, single-throw (SPST) dry contact switch

Installation Flexibility

The AFS Series switches are designed for easy installation in any vertical plane, ensuring accurate pressure measurement. They come equipped with connectors for ¼" OD tubing and optional adapters for other tubing sizes, allowing for flexible setup in various duct configurations.

Final Thoughts

The AFS Series Differential Pressure Switches are a robust and reliable solution for ensuring the safety and efficiency of HVAC systems. By accurately monitoring duct pressures, these switches help prevent system failures and maintain optimal operating conditions, ultimately contributing to energy savings and system longevity.

For more information or to place an order for the AFS Series, please visit the Belimo website or contact our sales team.

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