Cleveland Controls AFS-951-1 Switch

The Cleveland Controls AFS-951-1 is a professional-grade air pressure sensing switch engineered for high-accuracy performance in industrial and commercial HVACR applications. Designed with a broad 0.05" to 12" WC set point range, this SPDT differential pressure switch provides exceptional versatility for monitoring positive, negative, or differential pressure across blower coils, filters, and combustion air systems. Housed in a rugged NEMA 4 enclosure, the unit is built to withstand harsh environments, offering watertight and dust-tight protection for outdoor or wash-down installations. The internal silicone diaphragm ensures long-term stability and precise set-point repeatability, while the field-adjustable calibration screw allows for fine-tuned switching thresholds. With a high electrical rating of 15A and 1/4" NPT sample line connections, the AFS-951-1 sensing switch is a reliable choice for combustion air proving and low draft cutoff safety circuits, ensuring the HVAC pressure switch operates within spec even under demanding field conditions.

• Versatile Pressure Monitoring: Capable of sensing positive, negative, or differential pressure, making it a universal solution for various air handling sequences.
• NEMA 4 Rated Protection: The weather-tight steel housing allows for installation in damp or dusty environments where standard NEMA 1 switches would fail.
• Precise Set-Point Control: A wide range of 0.05" to 12.0" WC allows for granular adjustment, crucial for sensitive industrial air handling applications.
• Durable SPDT Switch: Features snap-acting SPDT contacts rated for up to 277V AC, facilitating easy integration into control and alarm circuits.
• Reliable Diaphragm Design: The silicone diaphragm is optimized for vertical mounting to maintain high-accuracy switching and minimize set-point drift.

• Can this switch be used to monitor filter loading? Yes, the AFS-951-1 is commonly piped as a differential pressure switch to detect pressure drops across air filters, signaling when maintenance is required.
• How do I adjust the set point in the field? Remove the protective plug on the NEMA enclosure and use a flat-head screwdriver to turn the calibration screw; clockwise increases the set point while counter-clockwise decreases it.
• What is the best mounting orientation? For maximum accuracy at the lowest set points, the switch must be mounted with the diaphragm in a vertical plane.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.