Dwyer Instruments AAFS | Adjustable air flow paddle switch
The Dwyer AAFS adjustable air flow paddle switch proves duct airflow across a field-adjustable 200-1800 FPM range. It features a stainless steel vane, IP65 ABS housing and a heavy-duty SPDT contact rated 15(8) A at 250 VAC, making it suitable for fan proving, air handlers, exhaust systems and duct interlocks. Genuine Dwyer Instruments stock at General Tech Services LLC, Saudi Arabia, with free Saudi Arabia shipping. Request a quote in under a minute - call +966 569 289 544.
Product Overview
When a supply fan belt snaps or an exhaust fan trips, downstream equipment may continue operating unless airflow is monitored. The Dwyer AAFS provides a simple way to confirm that air is moving through the duct before heaters, dampers or other equipment continue operating.
The AAFS is a paddle-type air flow switch that uses a stainless steel vane to detect airflow. As air moves through the duct, the vane operates an SPDT switch when velocity reaches the selected trip point.
The trip point can be field-adjusted anywhere from 200 to 1800 FPM using the internal set-point screw. This allows technicians to match the airflow proving point to the requirements of the installation without a separate recalibration procedure.
The switch features an IP65 ABS housing for protection against dust and water jets. Its stainless steel vane, brass lever and galvanized steel base are suited to demanding HVAC and plant-room environments. Ambient operating temperatures range from -40 to 85°C, while process air temperatures range from -10 to 85°C.
The SPDT contact is rated 15(8) A at 250 VAC, making the AAFS suitable for many control, alarm and equipment interlock circuits. Wiring is made through screw terminals via an M18 x 1.5 cable gland. The unit weighs approximately 380 g and is designed for horizontal duct-flow installations.
Key Benefits
- Field-adjustable airflow trip point from 200 to 1800 FPM
- Internal set-point screw for adjustment without separate recalibration
- IP65 ABS housing for protection against dust and water jets
- Stainless steel vane and brass lever for long service life
- Galvanized steel base for industrial HVAC installations
- SPDT contact rated 15(8) A at 250 VAC
- Wide ambient operating range of -40 to 85°C
- Process air temperature range of -10 to 85°C
- Screw-terminal electrical connection with M18 x 1.5 cable gland
- Suitable for fan proving, duct heater interlocks and airflow alarms
- Genuine Dwyer Instruments stock with free Saudi Arabia shipping
Need help selecting the correct airflow set point? Call +966 569 289 544 for assistance.
Who This Product Is Best For
- HVAC contractors proving airflow on AHUs, FCUs and fresh-air units
- Facility teams interlocking duct heaters so they operate only when airflow is present
- Kitchen and car-park ventilation systems requiring fan-failure alarms
- Panel builders needing an air flow switch with a heavy-duty 15 A contact
- Maintenance teams replacing worn or corroded paddle-type airflow switches
How to Use / How It Works
- Mount the AAFS on a horizontal duct run with the vane positioned perpendicular to the airflow.
- Connect the SPDT contacts to the required control, interlock or alarm circuit through the M18 x 1.5 cable gland.
- Start the fan and adjust the internal set-point screw until the switch operates at the required airflow velocity.
- Stop and restart the fan to verify that the switch changes state correctly.
- Confirm the control or alarm response and close the switch cover after commissioning.
Frequently Asked Questions
What airflow range does the Dwyer AAFS cover?
The Dwyer AAFS has a field-adjustable trip range of 200 to 1800 FPM.
Do I need to recalibrate the switch after changing the set point?
No separate recalibration is required. The internal set-point screw is used to adjust the airflow trip point in the field.
Can the AAFS handle hot rooftop ducts in Saudi Arabia?
Yes, within its specified temperature limits. The ambient operating range is -40 to 85°C, while the process air range is -10 to 85°C.
What load can the switch contact carry?
The SPDT contact is rated 15(8) A at 250 VAC, making it suitable for many airflow interlock and alarm applications.
Is the Dwyer AAFS suitable for fan-failure monitoring?
Yes. The switch can detect loss or reduction of duct airflow and can be connected to a control or alarm circuit for fan-proving and fan-failure applications.
Should I choose the AAFS or the Dwyer 530?
The AAFS provides a wider 200-1800 FPM field-adjustable range and an IP65 ABS housing. The Dwyer 530 is a different airflow switch design with a die-cast body and a 400-1600 FPM range. Select the model according to the airflow range, enclosure and installation requirements of the application.
Is the Dwyer AAFS genuine Dwyer stock?
Yes. General Tech Services LLC supplies genuine Dwyer Instruments products in Saudi Arabia with free Saudi Arabia shipping. Call +966 569 289 544 for pricing and stock availability.
Request a Quote Today
Get the Dwyer AAFS adjustable air flow paddle switch delivered free anywhere in Saudi Arabia.
Call +966 569 289 544 | www.generaltechshop.sa
