Cleveland Control AFS-227-161 Switch

The Cleveland Controls AFS-227-161 is a professional-grade proving switch engineered for precision air pressure monitoring in HVAC and energy management systems. Designed to sense positive, negative, or differential air pressure, this SPDT airflow switch features an adjustable set point range from 0.05" ± 0.02" to 12.0" w.c., providing the technical flexibility required for complex duct static pressure and fan proving applications. The unit utilizes a silicone-compatible diaphragm and a plated housing for long-term reliability in environments containing air or non-corrosive combustion by-products.

For optimal performance, the AFS-227-161 must be mounted with the diaphragm in a vertical plane to maintain its lowest operating set point. This high-performance pressure sensing switch supports 120-277Vac electrical loads and is rated for a maximum pressure of 0.5 PSI. Field technicians can easily integrate the unit into existing control loops using the 6-32 screw terminals and standard 1/4" OD metallic or semi-rigid tubing connections. This robust HVAC air pressure switch is a standard solution for building automation and industrial process cooling where accurate flow verification is critical.

Key Benefits for Contractors:

• Broad Set Point Range: Field adjustable from 0.05" to 12.0" w.c. to handle diverse differential pressure requirements.
• Universal Compatibility: Senses positive, negative, or differential pressure, reducing the need for multiple SKUs on the service truck.
• Simplified Installation: Features SPDT contact arrangement and three screw top terminals with cup washers for secure electrical termination.
• Industrial Durability: Rated for a minimum of 100,000 cycles at maximum electrical load and 1/2 PSI maximum pressure.

Common Questions:

Can the AFS-227-161 be mounted horizontally?
To ensure the 0.05" w.c. set point accuracy, the switch should be installed with the diaphragm in a vertical plane. Horizontal mounting may cause the weight of the internal components to shift the calibration set point.

What type of tubing is recommended for the air sampling connections?
The integrated compression ferrule and nut fittings are designed for 1/4" OD rigid or semi-rigid tubing (copper, aluminum, or plastic). For runs over 20 feet, use 1/4" ID tubing to prevent pressure drop lag.

Is this switch suitable for detecting combustion flue gas?
Yes, it is rated for air and combustion by-products that do not degrade silicone, making it suitable for draft proving on many high-efficiency furnaces and boilers.

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.