Description
Dwyer PAFS-1004 Averaging Flow Sensor Overview
The Dwyer PAFS-1004 Averaging Flow Sensor is a precision instrument engineered for accurate airflow measurement in HVAC, building automation, and industrial air handling applications. Designed for use with air and compatible gases, this sensor uses a multi-point averaging pitot tube design to deliver reliable, repeatable differential pressure signals that accurately represent the mean velocity across the duct cross-section — even in installations with less-than-ideal upstream straight-run conditions.
Key Features
- Multi-point averaging pitot tube design for accurate mean velocity measurement
- 7-21/32″ insertion length for compatibility with a wide range of duct sizes
- Compatible with air and non-corrosive compatible gases
- 1/4″ I.D. process connection tubing
- 3/8″ O.D. tubing process connection for easy field installation
- Generates a differential pressure signal for use with compatible transmitters, controllers, or manometers
- Durable construction suited for commercial and light industrial HVAC environments
Application
The PAFS-1004 is ideal for measuring airflow in supply, return, and exhaust air ductwork in commercial HVAC systems. It pairs seamlessly with Dwyer differential pressure transmitters and controllers to provide a complete airflow monitoring solution. Typical applications include air handling units (AHUs), fan coil units, VAV systems, and building automation system (BAS) integration.
Installation Notes
- Insertion-style design mounts directly into duct wall for straightforward field installation
- 3/8″ O.D. tubing connections allow for standard pneumatic tubing hookup to downstream instrumentation
- Suitable for horizontal or vertical duct installations
- Verify duct dimensions and wall thickness prior to installation to ensure proper insertion depth
Product Specifications
- Brand: Dwyer
- Model / SKU: PAFS-1004
- Insertion Length: 7-21/32″
- Media: Air and compatible gases
- Process Connection: 1/4″ I.D. / 3/8″ O.D. tubing
- Sensor Type: Averaging flow (multi-point pitot)









